I love the whine of superchargers, from the characteristic howl of the Merlin V12 in an old warbird, to the scream of top fuel drag racer, blowers rock.
Clearly it was time I owned one, and in another dangerous moment of ebay browsing I came across a modestly priced Jaguar XJR, first of the V8 supercharged cars, 1997 vintage.
The car looked ideal, sensible mileage, good maintenance, but crucially cosmetically challenged which brings the price down nicely without effecting performance. Also the numberplate was probably worth as much as the car, so in theory I could sell the plate and make most of my money back…
Well, you’ve got to dream.
And in this case my dream was to buy a car cheap, strip out as much weight as I could without actually putting much effort in and then take it racing, or at least a track day or two.
So I did what any sensible and careful car buyer would do, I placed a bid without looking at the car and forgot about it. Oh, hang on, no, that’s the opposite of sensible isn’t it. Yes, often get those two mixed up; sensible / stupid.
The following day I received the email saying I’d got the car, so we had a little road trip to plan. Diana gave me a lift to Kent, just over 100 miles away from home, in her fabulous BMW 840. It was quite a fun road trip, the sun shone, the motoway food was edible, the exhaust roared.
The guy selling the XJR clearly enjoyed driving the car, judging by the tyre wear, which is as it should be. The car was a little tatty, a few dents, a bit of mould but seemed to be mechanically sound. Our five year old son thought it was lovely and spent a good ten minuets checking out how bouncy every seat was.
Documents were exchanged and off we set back home, but the very first thing to do was put some fuel in, the gauge was right at the bottom. The fuel station was a few miles away so I took it easy, it’s one of the exciting things about buying a second hand car; you don’t know how accurate the gauge is and whether you’re going to run out of fuel before you reach the petrol station, quite a fun game.
Soon the green glow of a fuel station arrived, I pulled in and pressed the button to release the fuel filler flap. Absolutely nothing happened. Yes, unbelievably the electronic flap release system had failed, imagine that, and old car with dodgy electrics, got to be a first…
Now there was quite a queue forming behind me at this busy fuel station, not a huge amount of patience present there at that time, which added nicely to the drama. I opened the boot and ripped the side trim out to expose the release solenoid, bent the bracket out the way and pulled the release mechanism by hand. Sadly no one in the queue seemed to appreciate this and kept scowling pointedly.
Anyway, with a full tank of motorway priced fuel we set off for home. On the slip road onto the motorway I gave it full throttle and the car responded with a very civilised yet substantial flow of thrust. I was quite pleased with this until I looked in the mirror and couldn’t see Diana’s 840, not because it was lagging behind, but because it was completely obscured by the thick smoke that had belched from the XJR exhaust. Hmm…
I knew the previous owner had used the car for short journeys, so there was probably some oil in the intake from condensing crank case vent gas, probably, so the smoke could be from residual oil, maybe, so it could be ok, perhaps, and might just need a good blast to clear it out, hopefully. Only one way to find out, more full throttle.
And sure enough, after a dozen high power blasts it did start to clear. Which was nice.
We made ‘good progress’ on the way home, the lead swapping from 840 to XJR several times, both cars are huge fun to drive but in very different ways. The 840 has a sports exhaust, it barks and growls, the ride is firm yet the steering has only modest feedback, it goes like stink and looks like a rocket ship. By contrast the Jag is near silent, the ride is exceptionally smooth but sharpens up when you throw it some curves due to the two stage dampers, it corners very well, more roll than the 8 but with more feedback in the steering, a gentle giant but the full throttle thrust is substantial and constant as the speed rises. And it has 90bhp more than the 8, but they have similar weights, something in the region of 1800kg.
The Jag’s interior is lovely, bright leather and dark wood, very comfortable and a pleasant place to be. The only down side is that it will all have to get ripped out as we enter phase two. It does seem a shame to throw all that loveliness away, but to be fair the seats are worn, the headlining held up with lots of tiny pins and the seat belts are mouldy. In fact there is a distinct whiff of mould all round the car and the carpets a slightly moist. Not encouraging.
Once home I gave it a bit more of an inspection, plugged the computer into it’s diagnostic socket and had a rummage about. Turns out the mileage isn’t genuine, this may be because it has had more than one replacement dash units due to the tendency for them to burn out. Not sure what the real mileage is, probably about 160k, not that this matters for this project.
Then, a few weeks later, I was asked to join the Coventry Motofest team as the Live Action Director, giving me the job of closing the ring road and the largest car park in the city and turning them both into race tracks for the event! This meant two things for the Jag, first I didn’t get to use it much as I was somewhat busy, secondly I decided to use the Jag as the Motofest Pace Car, which is basically a track day car with flashing lights on. Easy.
The Jag is left unused over Christmas, and on returning I find that the whole interior has sprouted a blanket of mould and fungus, the carpets are particularly lively and the seatbelts are now a multi coloured patchwork, I guess there must be a lot of nutrients in 17 years worth of executive belly sweat.
Eventually the sun came out and I set aside one weekend to do the initial strip out. First I set about the boot, obviously the trim had to go but I wasn’t expecting much weight there, but as it turns out there was over 15kg of fluff and rags in there. Then out came the tool kit and spare wheel. Now, the last owner had told me the car had a ‘matching spare wheel’ but seemed a little self conscious when he said it. The reason may have been that the wheel was utterly f##ked, the rim was badly damaged and in some parts it was missing completely, great chunks of aluminium alloy had been ripped off. The tyre had massive cuts in, right down to the cords which were exposed and rusting merrily. I have only ever seen wheels and tyres in this condition in a scrap yard. Which is where I took this one.
The strip out continued with some help from my 5 year old son who set about the CD changer with a socket set, good training. In total about 80kg came out of the boot that day.
Next it was the interior’s turn. This had to happen in a set order because the electric sun roof mechanism can only be removed when the front seats are out. And my lord those front seats are heavy, about 40kg each with all the electric motors and air bags etc. Once the front and rear seats were out and scattered on the drive way, Diana observed that they would look really good in the summer house that I hadn’t built yet.
Next the sunroof came out, which is also quite heavy. My initial thought was to use the sunroof outer panel to fill the gap in the roof, just running a bead of weld round it, but even the panel was heavy with strengthening beams in, so I abandoned that idea and riveted in a sheet of ally instead.
I wondered if it was worth taking the center console out, but the race seats would foul against it so out it came. Again I was surprised how heavy this piece of trim is, turns out it is made on a steel shell which seems a bit excessive, it’s not like the trim is structural.
Whilst I was on a roll I took out the radio (5kg) and some other bits and bobs which all added up. In total I took out about 250kg from the interior!
The seating posed an interesting challenge, I needed something supportive and tall for me, most race seats are too short in the back for me, but as this was going to be the Pace Car I needed a passenger seat that could accommodate a variety of body shapes. Corbeau stepped up to the challenge and supplied two ex-display seats. I bolted the passenger seat directly to the floor, fairly well back much as they do in real rally cars, I then bolted the drivers seat to the original jag seat frame to give it a little more height and make it adjustable.
I bought a 6 point race harness from Sabelt for me, somewhat overkill but it looks nice…
The passenger gets a four point supplied by the most excellent Matt Philips of Retro Warwick fame. The shoulder straps bolted onto the original seat belt mounting points on the rear bulkhead, but the lap belts needed a few holes drilling in the floor pan and some large spreader plates. All the seat and belt mounting was made a little more challenging by the fact that the floor under the seats is double skinned with an upper panel that slopes downward to the rear.
Now, because I have no money the plan was to leave the suspension and brakes standard, after all it already handles well and with the weight loss the brakes should be more than adequate. OK so it’s a fairly dodgy theory, but when you’re skint it makes sense. Of course this does mean that with the weight loss the car will be sitting pretty high on it’s springs, which would look silly, so I had a cunning plan. If you search the web for ‘Dakar Jaguar XJ’ you will see loads of rather fabulous pictures of an old Series 3 XJ hammering through the desert rally, quite inspiring. And of course it had raised suspension…
So all I needed to do was fit bigger tyres and I had an extremely unsuitable rally car! OK, so there’s a hell of a lot more to making a rally car than that, but this is just a bit of fun so I am quite happy to gloss over all those pesky details.
Although the car came to me with 18″ wheels, the choice of off road tyres is greater for the optional 16″ wheels, so I picked up a tidy set off ebay for next to nothing and set about acquiring a nice set of All Terrain tyres from our friends at Falken. I’d measured the wheel arch clearance and found that I could just about get away with 30″ diameter tyres if I made some subtle bodywork modifications with a big hammer. This compares to the standard tyres of 26” diameter, raising the car by a further 2” and filling the arches rather nicely.
It would still be a bit tight near the bulkhead, so just in case I also ordered a set of road tyres for the 18″ wheels, just an inch bigger than standard.
Then I hit an annoying problem, the original wheels wouldn’t come off! I tried encouraging them off with a big rubber hammer, with pry bars, soaking in WD40 for a week and even driving the car up and down a private road with the wheel nuts loose. It took a whole day to get the wheels off! All because who ever had fitted them hadn’t lubricated the mating faces, such a simple piece of maintenance, why do people skip it?
So, with one side on jacks I finally got to offer up the monster tyre to the front wheel arch, and sure enough it fouls on the front end of the sill quite hard, but luckily the sill extends quite a few inches in front of the bulkhead, meaning that the leading section adds nothing to the car’;s strength and is there merely to support the front wing. So I trimmed it back to the bulkhead, and in so doing successfully located the rust! The inner side of the sill was heavily corroded at the front end, additionally where the footwell met the sill there was a thin line of rust. Not ideal, but on the other hand it doesn’t make a huge difference to the vehicle’s strength. If the rust had been a bit further back, under the A pillar for instance, then it would be a different story, luckily that area was solid.
Also the wheel arch rim was in the wrong place and the lip just touched the tyre, with with some gentle persuasion with a big hammer the arch flared out nicely. It’s quite subtle but the top of the arch is an inch further outboard than standard. The rear edge of the front arches were unfortunately rotten, bit of a lace effect. To make it look a little bit less terrible I covered that bit in tank tape, which made it look just as terrible but now it looked like I was trying to hide something.
So now I had the wheels on, seats and harnesses in and a not leaking roof. Clearly time for a test drive! Pulling out of the first T junction onto the main road the weight loss was immediately apparent, the thrust was significantly higher despite the taller gearing from the monster tyres. It was obviously louder in the cabin without the sound deadening, but still civilized, which would prove vital at Motofest when using all the radio communications kit on the track. Going into a swift corner revealed that the chunky off road tyres tended to drift significantly, as expected, in a rather entertaining sort of way. But the tyres and the ground clearance mean that this venerable old Jag can clip apexes onto grass verges on a race track should the need arise, in fact it could probably drive straight through gravel traps!
An unexpected benefit is that parking and manoeuvring is easier as now it can drive over curbs.
Returning home the steering became heavy, and a pool of steering fluid on the drive indicated that the power steering cooler hose had burst somewhere inconvenient. The leak was from the union under the air filter in the front drivers side of the engine bay. The air filter was covered in steering oil which had sprayed up through a large hole in the airbox, the hole was caused by the mounting lug being ripped out, clearly something had been going on here. Further stripping revealed the car had had a frontal impact in it’s past, it had been pulled straight and a new front right wing fitted, although solid it was a cheap repair, with damage to the fog light and indicator wiring as well as the fore mentioned steering cooler. I had to take out the whole radiator pack, intake and chin spoiler to get it fixed. Whilst there I replaced the front drive belt and a couple of pulleys that were starting to make noise, I removed the air conditioning radiator and some other bits it no longer needed. I also left the lower headlight trims off, because I think it looks better without them. In fact it look quite good with no grill either, but then it looks somehow less Jaguar.
At this stage it needed a name, so I asked the Twitter and Facebook community for ideas, based on the car’s ability to push on through poor road surfaces with unreasonable haste. One suggestion caught my imagination; Dreadnought. Dreadnought was a class of battle ship from about a hundred years ago, it was more heavily armoured and faster than previous ships, and although that class of ship saw action the original Dreadnought itself was never used in a real battle. In other words it was heavy, fast and looked the part but was never tested in combat. My jag is heavy, fast and although it looks like a rally car it will never be in a real race.
It also fits into my ship based race car theme, as my last race car was a Jaguar XJ-S V12 called the ‘Black Pearl’ (see previous post for details).
In time honored tradition all the work was finished at the last minuet, and I drove up to Coventry the week of Motofest with several more things still to do. As I set off, driving round the lanes of Cambridgeshire was an absolute joy, then it was onto the A14 and M6 for the 60 mile trip to Cov, this all passed pleasantly enough but just as I slowed for the exit junction to Coventry a helpful warning light pinged onto the dash telling me the gearbox was unhappy, and suddenly I only had one gear, third! The symptoms pointed to gearbox fluid loss, I limped it very gently back to a friend’s house in Coventry where I could test it, Nick is used to race machinery as he races in the British Cross Country Championship in a car called Insanity 2. Cunningly there is no dip stick on the XJR’s Mercedes gearbox, although one can be purchased. I used a bit of wire and found that the sump was all but dry, fluid had been squirting out from a fluid connection on the radiator pack, a quick investigation revealed there was no O ring in the joint any more! By an utterly bizarre coincidence Nick had an old Jaguar X308 radiator pack in the shed that he was thinking of adapting to use on his Land Rover, even more bizarrely it still had an O ring in the hole where the fluid pipe goes! What are the chances of that?
Of course I also needed quite a lot of transmission fluid, now these boxes use a specific synthetic oil that can be tricky to get hold of. Luckily another chum, Franc the guru of Land Rover engines, happened to have a few spare bottles because his Jag also used the same fluid. Another bizarre coincidence.
With that all sorted it was time to fit the all important stickers, the most important one being the Pace Car and Motofest ones that had been cut specially for me by Nathan Ward of Golden Bull Racing fame. There is an art to applying large stickers without getting creases and bubbles in, you apply soapy water first and squeegee it out from the middle, using a heat gun to get it to flow to the curves of the car. As you can see I am rubbish at this and should have left it to the professionals. This is made more embarrassing by the fact that some of the stickers are from Missions Motorsport, the forces charity that uses motorsport to rehabilitate injured soldiers and who also run a very successful graphics course, they trained guys who now fit the graphics onto Formula 1 cars. They would also be at Motofest training volunteers how to do a few stunt driving manoeuvres, so they’d see what a mess I made of the graphics on Dreadnought. And yes, they did verily take the piss.
I also had to wire in the amber flashing lights kindly supplied by Jon Fry of Northants 4×4 club. He is a rally marshal and would bring his Discovery as the course closing car, more of that later…
All in a rush the big day of Motofest arrived, I’d been working past midnight for weeks and was up until 2am rewriting the running order. After a quick sleep I was up at 6am to check the road closure was going to plan, driving Dreadnought through the deserted city streets felt like the beginning of some cult film, I had the windows open to hear the supercharger whine and the drone of the tyres more clearly. It felt good.
Soon participants started to arrive, by 9.30 we had a closed road, I’d done the driver briefing and Darren of Destination Nurburgring fame was doing the signing on. The radio coms truck was set up, we had radios in all the control cars and we had teams on the entrances and exits controlling traffic. Time to deploy the marshal teams, leading the convoy of Land Rovers in Dreadnought round the deserted ring road was an interesting moment, this was the beginning of something special. We started the event with a few parade laps of classic and performance cars, sticking to 40mph and waiving to the small crowds building at the spectator points. I was at the front in Dreadnought and Jon was at the back in his Discovery 1 Tdi, that way we made sure no one went the wrong way or got left behind. In the afternoon we picked up the pace, with race cars running at higher speeds, demonstrating a small amount of their capability. Dreadnought coped with high speed cornering beautifully, drifting very controllably. Jon’s Discovery however may have not been quite so used to high speed cornering, but it kept up…
One memory will stick with me for a very long time, seeing an ex-BTCC Rover SD1 V8 in a long line of very fast race cars in my rear view mirror as I glided Dreadnought through the roundabout on junction 1, the crowd cheering and taking pictures.
In all Dreadnought put in 107 faultless miles hacking round the ring road that day. What a day.
Then it was a return to more mundane duties, for the next week I commuted to work in it, the only down side being that the wings on the race seat make side viability at T junctions a little tricky, that and the lack of air conditioning on a hot summers day.
Since then it has been used for some local trips and also appeared at Kimbolton Fayre along side Diana’s fabulous BMW 840, the fayre is the largest charity classic in the East, apparently, with over 800 classic and performance cars, well worth a visit.
We also took it to Santa Pod for a RWYB day, it managed a 13.8 second standing quarter mile with a speed of just over 100mph. Not bad for an ebay special!
So, mission accomplished. Dreadnought had a month and a bit of MOT left and so I put it up for sale in August 2014, it went to a new home at an Oxfordshire racing company where I’m sure it will continue to make people smile.
Here’s one from the archives, originally printed in 2006 in Classics Monthly magazine, but now with a short update at the end.
The original target – to be on the grid at Silverstone in a classic V12 racing car for less than £3000.
A full English breakfast sits before me as I stare out the window daydreaming about the great races of yesteryear. Last night on telly they showed a touring car race from the 60’s and the sight of Lotus Cortinas two abreast into Graham Hill bend at Brands Hatch was amazing. Even more stunning was Tom Walkinshaws qualifying lap at Bathurst in the 70’s, my god that man had no fear, cresting a blind left hander on two wheels at full power!
At that moment I had a revelation. I could actually go racing myself, ok, not F1 but certainly race a classic and evoke the atmosphere of those great days. By Jiminy, I’m going to do it. And do it in a V12 Jaguar, no less, armed with several spare weekends and an old cantilever tool box. What could possibly go wrong?
I was pleased to discover that some cunning chaps at the Jaguar Enthusiasts Club (JEC) had designed a race series for XJ-Ss. I have always fancied an XJ-S ever since I saw Joanna Lumley in one. The mission statement for the series is to allow enthusiasts to race their own cars for a sensible budget and above all ‘To have fun’. I like that.
I downloaded the race regulations before doing anything dangerous, I cant stress enough how important this was. There are classes for standard cars (both V12 and for 6 cylinder), that keep costs down, and classes for modified cars, which don’t. This is sound thinking, the car already has great handling, good brakes (when cool!) and, of course lots of power. Importantly it also has a very strong and stiff shell, which keeps the suspension working properly and means that you are (relatively) safe in most forms of popular motor sport accident. Class F for ‘Standard V12 5.3/6.0 Litre’ was the cheapest one for me. I am nothing if not cheap.
I took a deep breath and joined the club, registered for the championship and put an application in for the first race at Silverstone. The countdown begins..
12 weeks to go.
The absolute minimum spec for race preparation involves little more than painting the tow bracket yellow, fitting a race harness, fire extinguisher and putting a sticker on the door announcing ‘ignition on steering column’! but you cannot just take a road car, fling it around a track and expect it not to break, because it will, probably by not braking…
It became clear that I could make a good solid basic (back of the grid!) race-car by doing the following modifications:
Uprated brake pads and fluid to combat fade at very high temperatures.
Large air intake, standard has restrictive venturi.
Remove centre exhaust silencer.
Race engine oil to hold it all together at 6500rpm.
Improved cooling, standard is marginal.
Adjustable front dampers to firm things up a bit.
Remove as much weight as I can within the rules.
Use the series control Toyo tyre.
Mandatory safety mods, such as a plumbed in Fire extinguisher and racing harness. Others (such as a roll cage) are not mandatory but obviously sensible, after all, big cats should be caged…
Having digested that lot its time to make a budget. As I am not rich, this will make or break the project. If not realistic then I stand a fair chance of getting half way there and running out of money, that’s when you see adverts on Ebay saying “unfinished project, 90% complete”. I Don’t want to end up like that.
The basic budget is £1500 for a good car and the same for modifications.
There is some flexibility in the budget, for instance I could buy two spare race tyres and not do the track day. We also allow £500 for contingencies which I don’t intend to spend. I will be driving the car to each race so saving on the cost of a trailer, bit of a risk.
Before going out and buying the first XJ-S I could find I restrained myself and did some research, which proved vital, starting with magazines and the club web site/forum.
I found out that I needed to check a few critical areas
Rust at the rear and front end of the sills, where the trailing arms bolt on to the body and on inner wing at the damper mount area (will be worse than it looks, double skinned nightmare).
Oil leak from crank rear seal.
Water pump leaks and bearing looseness.
Rattles on cold start up (engine worn, expensive and time consuming to repair).
Smoke on start up or on overrun with hot engine.
Overheating, ask if there have been any cooling issues.
Rusty front cross member under the radiator and front suspension subframe.
Clonks or whines from gearbox, or burnt smelling gearbox oil.
Smell of fuel in boot (may indicate rusted tank).
If the car has any of these problems then I would walk away and look for another one.
Other common problems are less important because they will be dealt with during the conversion; these include cosmetic faults, trim, tyres, hoses, brake pads and electrical gremlins. Some cars are born with problems and will never be reliable; some are so sweet they are practically blueprinted and that’s the one I was searching for. I found a 1987 model on ebay with 93,000 miles and as a bonus it had the twin headlight kit which will come in useful later, it looked good on paper so off I went to check it out. The owners were just quite simply splendid people. We were plied with cups of tea and talked about the history of the car; they had owned it for fifteen of its nineteen years. The car was kept in the garage under blankets!
Opening the bonnet revealed a industrial scrap compactor, it was as though someone had mistaken the cavernous engine bay for a skip and thrown in a dumper load of old pipes, hoses, wires and random thingys, then smoothed it all down with a rusty trowel. Don’t get me wrong, it was all in good order, the fluids were topped up and clean, there were no leaks and the hoses were in good condition etc, but the photos in the manual simply do not do it justice, it really is full! All XJ-Ss are like that, for instance, to change the front spark plugs it is best to remove the air conditioning pump! I quietly shut the bonnet and turned away wondering what I was thinking of.
The rest of the car had a little surface rust here and there, a sagging head lining and old tyres but was basically in surprisingly good shape.
It sported a new radiator, oil cooler, brake disks, front subframe, front cross member, rear calliper, battery and a centre exhaust. Which was nice.
The engine was quiet from cold and pulled strongly and smoothly on the test drive, with no worrying noises. It gathered pace quite rapidly and handled corners competently with a polite bow. The driving experience can only be described as magnificent, for the first time on the project I had a definite feeling that this was right.
I decided to go for it so I put in my maximum bid and did not look at it again until after the auction, which was tough. Luckily I won it for my limit of £1500 and so the next week I had my first XJ-S.
10 weeks to go.
Having spent a week driving round in splendid V12 opulence, it was with a certain degree of regret and trepidation that I was to start tearing it asunder.
First stop is to remove the interior, remembering that the regulations for Class F state that the trim must go back in, unless its in the way of the roll cage. Loose carpets must be removed. Weight is all important but I didn’t get too carried away with stripping every last ounce, for example I took a day to remove the first 50Kg but the next 50kg took a week.
Out came the centre console, heater controls and a radio retaining box thingy which is riveted into the dash and had to be drilled out.
The regs let me replace the drivers seat only, saving about 7kg, so the passenger seat will go back in later. The regs allow removal of the rear seat but again it proves to be disappointingly (9kg) light!
At this point I successfully locate the rust! There was a bodged repair to the inner wheel arch which let water into the rear seat pan which had rusted along a seam leaving a huge hidden rust lake.
Under the carpets I discover a distinctly aquatic theme, part of the window seal is leaking and water is dripping down the electrics into the foot well! As a temporary fix I tape up the lower edge of the windscreen.
Sound proofing on these cars is quite remarkable, both for its effectiveness and for what a sod it is to remove! There are different types in layers. Under all this glue and matting is the main wiring! So I had to be rather careful with the chisel! About 30kg of sound deadening came out and now there is plenty of clearance in the foot well for my left boot.
Doors present a few challenges. The trim card has lots of hidden screws and a tag behind the arm rest so it has to be lifted up before it comes off. The central locking solenoid and speaker add up to only 1 kilo, manual window winders would have saved another 1kg.
The electric mirrors hardly weighed anything and the saving with the racing items was negligible. Later I would find that having electrically adjustable mirrors whilst I was harnessed in would be invaluable.
Turning to the engine bay.
Starting in the middle I unbolt the heavy (15kg) air con pump and its silencer, yes the air con has a silencer. Also ousted were the fuel cooler, a/c radiator (which had rotted out), visco fan and associated tensioner (8kg)
There is sound deadening foam on the bonnet, I drill out the rivets and attack it with a garden hoe causing odd looks from the neighbours.
Finally, the boot is stripped of trim, spare wheel, tool kit and jack.
The brakes and steering checked out ok, as did the exhaust system.
Electrics were ok if tired. The critical circuits are ignition, fuel injection, starter, cooling fan, wipers and tail lights (nothing else matters!). The bodged immobiliser was removed (it only required swapping two wires to defeat!).
Luckily on this car most of the rubber pipes (which perish after about ten years) had been replaced because of the new radiator and oil cooler and fuel system. Bonza!
The cooling system is a whole different bucket of mice, the Jaguar official service procedure involves adding an annual bottle of Barrs Leaks! This coats all the places you don’t want it, in such high doses. So the radiator, engine and heater core are checked for leaks and flushed. Some people go to the extreme of fitting coolant filters in the top hoses.
Throttle cables are often forgotten but obviously vital for survival, it turns out to be in good condition and gets oiled.
Right, the car is now in bits, but about 130kg lighter. Probably time to start putting it back together then. After a cup of tea, obviously.
8 weeks to go.
Sitting in the car as standard, my head hits the roof. Add to this a crash helmet and a roll cage and I will have to remove four vertebrae!
My solution is to use a high back seat, usually used in off road racing (Ebay, £40). It has a near vertical back which means I can fit it with the rear on the floor and the front on the 4 inch high cross member giving my preferred recline.
I chisel out the rear outboard seat mounting from the floor, sit the seat down and sit in it with the crash helmet on to check the fit and clearance.
I push the seat as far to the left as possible. Now the rear left seat mount is hard up against the transmission tunnel, so I fabricate a bracket that bolts to the seat and then the whole assembly bolts to the car using the original mounting points. The right hand mount is much more simple and bolts through the floor.
The gauges should be easy to read even when I am not looking at them. In the good old days gauges had needles and they were arranged so that all the needles were vertical when all was ok. We are very good at detecting horizontal and vertical lines, which may go some way to explaining tartan.
In this car, however, there is a small rev counter which is not easy to see and the temperature gauge (remember these cars are renown for overheating) is a particularly useless linear affair which reads just above cold when the radiator is at 90 C! So a reading of Normal would only be reached when the engine has seized and caught fire!
For now I will simply stick red tape next to the gauges so that my eye naturally falls on the relevant part, with a small line at danger temperature and min/max rpm.
There is a huge range of harnesses available but very few of the mandatory FIA approved 3 inch items below £100, cheapest I found was £95 four point item, but in the end I went for a TRS five point. The crotch strap pulls the lap straps down, so they stay over the pelvis and don’t ride up over soft tissues, preventing rupturing of various squidgy bits, possibly including the spleen. I have never really know what a spleen actually is or what it does, other than kill you if ruptured, which I guess is the key point here.
The lap straps are secured to the floor via eye bolts which I screwed into the original seat belt mountings. The shoulder straps will be rapped round the cross bar of the rear cage that is provided for just this purpose.
6 weeks to go.
To start with I do a very chap mod, I cut the ram pipes very close to the air box and spend a good half hour flaring the edges out to smooth the air flow into the box. Thus the intake area is tripled.
As an extra treat I fit new standard paper air filters. Years ago some colleagues tested standard paper elements against sponge and cotton performance filter elements. At the start of the test all the filters were flowing about the same so a standard one will be fine for a few races, particularly as a standard one is £6 and a performance one is £45, and I need two of them.
The throttle needs to have an extra return spring fitted, theory being that if the return spring brakes then you have a big accident, this will be checked by the scrutineers before every race.
The exhaust centre labyrinth type silencer is very slightly restrictive, so I removed it and fitted a significantly more free flowing bent piece of pipe. This leaves the rear straight through absorption type silencer only, but the result is still disappointingly quiet and civilised on the road.
The engine oil is replaced with Castrol RS 10/60 racing oil, and of course a new filter. Even expensive oils like Magnatec will break down under racing conditions, so I am told. Its bloomin expensive though, the V12 uses 10.7 litres so this is a significant investment. I eventually got it from Demon Tweeks, race championship registrants get a 10% discount card.
I add water wetter to the new 20/80 mix of glycol/water. People in the club claim this alone has dropped coolant temperatures by 10 degrees, I think it works by breaking the surface tension and allowing better heat transfer with the metal. Also, I fit second hand electric fans where the old air con condenser was, to stop the engine cooking just after a race. Finally I improve air flow out of the engine bay by jacking the bonnet open half an inch on some rather fetching home made (M12 bolts) bonnet pins.
Gearbox remains a GM TH400 auto box! Yes, I am racing an automatic (oh do stop laughing). Once you get the hang of them they do have some advantages such as being able to change up at full throttle. The problem is that there are less gears than in a manual so its harder to stay at peak power rpm. The torque converter is effectively hydraulically locked at high rpm giving minimal power losses and full engine braking. I will be manually shifting with the stick provided, but it does not let you shift into first above about 15mph unless you have the throttle floored, which is an issue if braking into a corner.
Now the seat is on the floor, the gear stick is a little high. Also, it wobbles due to its compliant rubber mounts. Bolting the selector directly to the trans tunnel improves things no end.
4 weeks to go.
As standard the Jag brakes are good. The problem comes with continued maximum use, races can be up to 20 mins and standard fluid will boil, the pads will catch fire and the disks will warp! Apart from that they are OK!
The standard (almost new) discs will be fine for now. I have chosen EBC Red Stuff pads which wont fade but will wear quickly, other racers use the harder Yellow Stuff pads but these are not suitable for road use.
Next up for change is the fluid (a complicated subject). The upshot from many discussions is that I have chosen synthetic (NOT silicone) racing fluid with a dry boiling point well above 300 C. The preferred one is Castrol SRF, but I went for the cheaper Motul RBF600.
To top this lot off I fitted Goodridge 600 series braided brake hoses which improved pedal feel and are better suited to the harshness of racing.
This went quite well until one of the rear calliper bleed nipples sheared off! This meant removing the calliper and drilling it out which took the best part of a day to fix, and this happened with only two days until the Mallory track day!
Suspension and steering
A sports steering wheel allows slightly quicker turns and improves feel. It also looks good. Steering rack bushes give a kind of disconnected feel to the steering, I replaced these with polyurethane bushes.
The suspension is basically very good, if rather soft. I am not going to change the springs yet, Collin Chapman was a strong advocate of soft springs and firm dampers to let the suspension move and do its work, who am I to disagree (oh dear, now I can hear Anny Lennox in my head…). I just fit adjustable front dampers which bolt in very easily.
For safety I have fitted an electrical cut off switch which stops the engine and isolates the car from the battery. The battery is in the boot and has a positive lead running down the left hand side of the trans tunnel and then up to two distribution studs, the switch cuts into this and sits nicely behind the gear selector.
There are two wires near the battery, which feed the engine management and fuel pump circuits, so I cut them and put in new wires from the cut off switch. Next I ran a new wire from the lower part of the switch to the ignition circuit and connected the alternator protection resistor (provides a load when the switch opens, without one the regulator gets confused and explodes).
2 weeks to go.
The rear bulkhead needs to be sealed to prevent any fumes getting in from the petrol tank, I riveted small ally plates over the various apertures.
The extinguisher and electrical cut off switch must be able to be operated by a marshal from outside the car, in case I am incapacitated or too stupid. T handled pull cables go on the scuttle at the MSA recommended position – base of the windscreen on the drivers side.
I cut a big hole and mount the two cables to an ally plate that I can screw on and I cut holes in the inner panel to finally get through to the interior.
Finally I wandered round with some yellow paint, stripes round the battery earth lead and I sprayed the towing eyes.
Possibly the most important component on the car. For this series we have to use the control tyre which is a Toyo Proxes T1-R.
When racing the tyre works very hard, deep tread blocks will move about a lot and thus get very hot, they will go off after a few laps and you skid. So I will have them shaved to 4mm depth, this should give me good stability and still last a few races.
I have bought a set of spare wheels for £50 which are half an inch wider than standard. I am staying with 15” rims because the 50 profile tyres drops the gearing about 11% thus helping acceleration. And its cheaper.
A day at the races.
Now its time to tune the driver so its off to the club track day at Mallory, for a bit of practice and to get to know how the car handles on the limit and indeed where the limits actually are.
In an ideal world I would check and adjust the suspension set up. Realistically, unless it really handles badly, I will just try to get some practice in
When changing the set up it is vital to approach this scientifically, everything effects everything else so we change one thing at a time. All the changes and lap times are then written down in what becomes the race car book of all knowledge.
I even borrowed a pyrometer (in infra-red temperature gauge) so I can check the tyre temps.
We arrived, a little late, and had to wait in a queue to get to the pits area which is in the centre of the circuit. It’s a lovely circuit, quite short and has a lake in the middle which James Hunt nearly drowned in.
We locate fellow JEC members and say hello, everyone is very friendly and soon advice starts pouring in. We then head off to the stewards office to sign on, you have to sign an indemnity form which basically states that you are aware it is dangerous and any accident is your own silly fault. That done, I have to attend a novice briefing which covers etiquette and safety stuff.
As it is my first time here, I am assigned an instructor who was very helpful indeed, he described which lines work, braking points etc.
Once the tyres had gone through their first heat cycle, it was time to push harder. The car seemed to grip and then grip some more, pushing me firmly into the side of my seat round the large corner, with the lake as run off. This is the first time I have heard the throaty exhaust at full tilt, spine tingling.
Tyre pressures seemed best at 30psi cold /34 hot which gave an even temperature, but the outer edge of the fronts was a little colder indicating that I need to stop fannying around and drive faster.
They have a weigh bridge there, with half a tank of fuel the car was 1606kg, which is a good start.
Also, they provided a scrutineer so that I had the privilege of finding out what was wrong before I got to the race! Generally it went well until he put his hand down the inner wing and there was a distinctive rusty crunching noise
1 week to go.
A quick call to Franc (aka Tree Beard) and I was on my way over to his house of wonder to use his welding kit, 15 hours later I left with a solid car! As is usual with these things the rust was a lot worse than it first seemed, the service history shows that the inner wings had been repaired before, at some expense, however we found no evidence of this, just rust! Makes you wonder.
For extra strength I put in replacement panels from 2mm steel between the chassis rails to the front damper mounts.
Turning to the rear, I made new panels for the sill end plates and the lower part of the wheel arch, this area has lots of panels joining together and the seams collect water, unfortunately this is a critical area as all the radius arm loads are put through here (ie, all the acceleration force). The result is not pretty but its definitely solid.
The next major job was fitting the stickers!
You know, they are not as easy as you might think. They are big, giving ample opportunity to trap air bubbles and get them all crumpled up, secondly the car is made from curves so the stickers wont sit flat and you end up with creases and folds.
The rules say we have to have a set size white square for the race numbers, one on each side and one on the bonnet. We must also have stickers for; JEC Racing, JEC club and the Toyo sponsors. In addition, I wanted my name on it and also we thought it would be a good idea to have some green stripes so that it could be easily picked out on camera, its distinctive and gives it the 70s look that I was after.
Every race car has to have a name. This one was suggested by Franc’s daughter who had decided that I was some sort of cross between Doctor Who and Captain Jack sparrow. Which I think is a compliment… Anyway, as the car was black, had a mind of it’s own, was largely a wreck but refused to die and handled like a boat, it was decided by the committee of chums that the car would be called the ‘Black Pearl’. And Rick went about creating the graphics for me, a superb job!
Fitting a roll cage is usually best done before the car is assembled at the factory, what with it being nearly the same size as the interior of the car.
I am using an MSA approved national B cage made by Safety Devices.
So, with no seats, centre console, roof lining or anything else to get in the way in the interior, I fitted the cage in order to mark out where the mounting plates must go. It took quite a lot of jostling to get everything to line up. It fitted about as well as ‘one size fits all’ trousers don’t. Then I marked the points where the cage feet met the car.
Now I take it all out again. I weld the nuts to the mounting plates, cut holes in the sill just big enough for the nuts to go in and then weld the four plates on the sills.
Then I put the cage back in again, I get everything loose assembled first then take up the slack in all the bolts, then progressively do up the bolts.
The bolts in the wheel arch go in from underneath, that way the bolt head gets covered in road salt and weather but the thread stays clean. Same goes for any bolts that go through the car outer shell such as those holding the seat mountings to the floor.
Standing back, it now looks like a proper race car, very nice.
MSA regulations, new for this year, require me to have a 2.5kg plumbed in fire suppression system with a minimum of one discharge nozzle in the engine bay and one in the cabin.
I fit the fire extinguisher bottle on top of the trans tunnel so that it is tucked into the back end of the centre console, where the rear ashtray used to be. The centre console has substantial reinforcement steel inside, so I cut most of that out, it’s a bit more wobbly now but its still central and still a console.
The transponder is bolted to the front of the car and sends a vehicle specific code used by the lap timing computers at the race circuit. It has to have a clear view of the ground and be less than two foot up. It also needs a 12v feed. I decide to fit it somewhere in the front left wheel arch area, but that’s about as far as I get before its time for a race!
0 weeks to go.
It had been only 12 weeks since deciding to go racing, in that time I had bought an XJ-S V12, stripped it, rebuilt it as a racer and driven it round Mallory park circuit for my first ever practice session.
My goal remains to complete one race, at Silverstone in a car that I prepared.
There is still so much to do and the big day has finally arrived, no more excuses.
I woke up at 3am. Then again about 4am and finally gave up attempting to sleep at 5ish. As my first circuit race approached, the totally overwhelming cocktail of excitement and fear kept me from any meaningful form of sleep.
I started faffing about wondering what it was that I had forgotten. Friends are vital to club racing, and several were pressed into service to transport all the tat that is associated with racing.
It took about 40 mins to pack the tools, spares, the jack, race clothing and paperwork into the jag. Ron was also following in his 205 with the race tyres and a collection of scrap iron and an angle grinder! You never know what you might need, or indeed what you might find in Ron’s car…
Unfortunately Ron’s car was a fairly knackered Diesel which made its rattly asthmatic presence felt quite well. As it was still before 6, the combination of this and a racing Jag starting up and manoeuvring off did cause some degree of curtain twitching. We apologise profusely for the inconvenience.
We were not the first to arrive, even though it was only 7:30, so seeing a few other XJ-S’s I parked up next to one with the same coloured stripe as mine, just to confuse people! Everyone was busy unloading, checking tyre pressures, drinking tea and other essential tasks. Even so, I found the other competitors to be a really friendly bunch and more than willing to give help and direction. There was a real atmosphere, difficult to describe, excitement, the sense of approaching battle, the smell of fuel and race oil, the sound of blipping engines and tools being used. The picture was of lines of race cars and transporters, people busy tweaking and preparing the cars, it was a picture I have seen before in magazines, but now I had made myself a part of it.
To be honest I felt like a fraud because I am new, I don’t feel like a racer yet, just someone who wants to be. Never the less it was such a good feeling just to have got this far. The sun was beaming down from a stunning blue sky, glinting of the cars chrome, it was a perfect day.
I took a quick stroll to get my legs working after the long drive to the circuit and had a look at the other cars, its amazing to see how they differed from mine, it seems that although everyone is agreed on what the key issues for these cars is, there is no one particular solution. Already I am getting ideas for modifications such as lowering the front and ducting cold air to the engine.
Its 8:00 and I am off to sign on and find out where scrutineering is.
In the stewards office I find some very helpful staff and once I explain that I am a bit new to this, they explain what I need to do in simple words as if talking to a child, which is about right actually! I sign an indemnity and hand in my race licence, they keep this safe and will record any misdemeanours and if I really cock things up then they can withhold it etc. More relevant, hopefully, is the fact that the clerk of the course will sign it to say I have been a good boy. Once I get six signatures I can ditch the novice cross, this is a bit like when you finally loose your L plates. They then give me a Programme, worth £3, which is nice.
Brilliant, job done. Off I trot back to the pits. Once there I remember that I was supposed to ask where the scrutineering was. Luckily our neighbour knew ‘see that big building next to us with Scrutineering written on it…’.
By now it was gone 9 and I scurry off to the novice briefing, required for anyone who has not raced at this circuit before. In the class room there was about 15 of us rookies, al talking about our adventures and excitement getting here. At 9:30 the briefing started with a friendly introduction backed up with a stern warning that no dangerous behaviour would be tolerated. We were presented with photocopies of the track layout, noting where the marshal posts were and where the entrance and exits are. Then they made a couple of rather useful points, one corner had aggressive rumble strips that would ‘take your wheel off’, oddly now I come to write this, I cant remember which one it was! Then they mentioned that the sand trap at the end of the back straight was extremely effective at stopping cars ‘ if you go into that, just get out of the car, you wont be able to drive out, you will have to wait to the end of the race and get winched out’! The session was concluded by the stewards wishing us well and lots of fun, which was nice.
Last min prep
Ron had changed the wheels for me and the remaining stickers had been attached. But I still had not attached the transponder, and feeling that my art of brinkmanship had been adequately demonstrated, decided to fit it above the front towing eye just before scrutineering.
Somehow it had become 10ish and the scrutineering bay was empty. I parked up in the bay and two chaps came out to appreciate my handy work, yes I was nervous, would they find something I had missed?
Again, I explained that I was a bit new and asked them if they could give me any tips etc. They were both very helpful, explaining what they were looking for and how best to do things. They checked the integrity of the car (all my lovely welding), that the seat was securely mounted and in good condition. They checked the condition and mounting of the harness and that it was certified and in date. They looked at the data on the fire extinguisher to ensure it was full, in date and the correct type. They checked my brake lights, side lights and high visibility rear light (or fog light as it is also known), that’s where we hit the first problem, the fog light didn’t work! Luckily this was just a fuse. That done, the ticket was issued and taped to the side window so track officials can clearly see you have been processed.
By the time this has all happened, the call comes over the tannoy for us to assemble ready for qualifying. There is something odd about the pits tannoy, it doesn’t matter where I stand I can never hear it clearly, it’s a bit like train platform announcements.
The assembly area is just before the pits area and is a copy of the starting grid. You form up here before a race or qualifying so that everyone is ready to go at the same time. The call to form up comes about 15mins before you are due to go out. The pro’s get there with just a min or so to go so they don’t have to wait too long. I, on the other hand, was so worried about missing the slot, got there with the full 15 mins to go.
Here I met Paul Hands who, never being one to mince his words, took one look at the car and said the front was too high, which it was. Then he went on to point out all the other things that need improving, very good advice I am sure, but rather poor timing!
The morning had gone so quickly up to now, this was the first time I had a chance to think about what I was doing. It’s a strangely peaceful moment.
So there I was, in a real racing car, dressed up like a real racing driver, waiting to go out for the very first time at Silverstone. Wow.
Then the whistle went, my heart started pumping harder, and we were off, moving in two columns onto the pit straight. I was surprised by lots of clattering coming from the underside of the car as all the debris, rubber and gravel, on the track hits the un-soundproofed shell.
We move out onto the pit straight for a warm up lap, sometimes called the green flag lap, this is where green flags are waved from every marshal post, no racing is allowed and the safety car is out in front with the fire car following behind us all. Warming up involves driving bloody fast, by the way. As we round the corner back onto the pit straight, the safety car peels off into the pit lane and the flags go in. Then it gets a lot faster and I try to keep up. Holding the throttle open as we hurtle past 100mph with a corner in view goes against all my instincts, my right foot starts to shake on the pedal, I know I have to go faster but something in my mind is screaming to slow down. The engine makes a superb noise, starting with a growl and ending with a roar, its smooth and inspires confidence.
All the video watching and learning the corners before hand counts for absolutely nothing out here! I try and follow the line of the car in front which works quite well, I am amazed how fast the car can go round corners with all the tyres howling in a graceful high speed four wheel drift. The brakes are splendid and powerful when up to temperature, which probably means I am not trying hard enough!. The gearbox is shifting well with under a seconds delay, but suddenly it makes a horrific grinding noise. It seems to be worse at peak torque so as long as I use part throttle from 4000 rpm I can increase to full throttle by 6000 rpm and its not too bad. But rather slow out of corners, hey I must be turning into a real racer if I already have excuses lined up!
I start to build confidence, or more accurately the feeling of complete confusion fades. I cant quite work out the right way to enter the hair pin at Maggots and try a variety of possibilities with varying degrees of success and a couple of sideways moments. By the fifth lap I was being passed, a lot, which made finding a good line a bit more tricky. Rear visibility is challenging, for example when reaching the end of the back straight (roughly 120mph) I glance in the rear view mirror I can see a rapidly advancing Class G car, I look back at the track and glance up again at the mirror and they have vanished. I turn into the left hander knowing that they will be in the process of overtaking me but I have no idea on which side or how fast. As I was going to turn in to the apex they appear on the left causing an abrupt change of plan. I go a touch wide which leaves me on the right going into the tightening right hander and have to slow even more to get round!
After a few more laps I am just getting my bearings and preparing to do a fast(ish) lap when the chequered flag comes out and its all over! Was that really 15 minutes? Well yes, it just goes so fast because my brain is in a warp.
Then we get one cool down lap. This is very important, as the brakes are so hot, as is al the metal of the engine, if you stop immediately after racing the heat soaking in will cook the diff seals, boil the brake fluid, roast the ignition system on the top of the engine etc. So I cruise round without touching the brakes, but get rather behind the rest of the pack who are trying to ensure the next session is not delayed.
As I turn into the pit lane I switch on the extra fan. Marshals direct the traffic all the way through the pit lane to the exit. I feel like I have done a good workout, I feel hot and I am breathing deeply. There is a million things racing through my mind, like can we fix up the gearbox enough to race, have the brakes caught fire, will the engine overheat before I get to the pits, most of it is silly worry but as an engineer I cant help that.
Pulling back into our camp, the team rush to open the bonnet and let the heat out, the heat haze is quite visible. I wave my infra-red temperature gauge across the tyres to see how I am using them. The left hand tyres get more work and are a touch warmer. The inside edge is a couple of degrees lower than the rest of the tyre indicating that I could run with a spot more camber but basically its not too far off.
Friends point out that we have a drivers briefing now back in the scrutineering shed and I am duly bundled off.
Its now 12:30 and the whole morning has gone in a frantic rush. The race is due for about 4:30 so we now have a long pause.
The gearbox mount is suspected of causing the grinding noise, it is a complex sprung mechanism which has a rubber isolator in the middle. Its difficult to see clearly but we think it is this rubber part that is breaking down and allowing metal to metal contact, it wont let go completely so there is no danger of the box falling out so the decision is made to continue as is.
After all that can be done to the car has been done its time for a full racing lunch! The top F1 drivers have a dietician and dine on nutritionally engineered techno food. I had beans, chips, pie and gravy, mmmmmmmmmm.
The results of qualifying have been published with photocopied sheets available from the stewards office. I am last, obviously, the grid arrangement has three columns and I am on the back left. My fastest lap was 1:32 giving an average speed of 63mph! The fastest chap in my class was Gordon Bobic with 1:21 at 73mph and the fastest overall was Derek Pearce with a 1:11 at 83mph. Yes I really was that slow!
I watched some of the other racing, the theory was to analyse how others took the hairpin etc but actually I just enjoyed watching some good racing and relaxed a bit.
My peace was shattered by the call to assemble for the race. I headed for the assembly area, marshals directed the cars to our grid positions and in no time at all we were going out onto the track. Here again marshals directed us to our grid position, which is essential for me because I sit so low that I cant see over the bonnet and the exact location of the grid markings becomes rather a mystery. I make a note of the car to my right and in front so that when we re-form the grid after the warm up lap I know where to stop!
With the safety car in front and the fire car behind, we roar off for a green flag lap. I am very aware that even though I am giving it some beans, the fire car appears to have no difficulty keeping up and wants to overtake me! The safety car peels off into the pits and we reform on the grid, I draw up parallel to the car to my right, I hope he knows where to stop!
On the gantry over the start/finish line, there are a number of red lights, they go out signalling the start of the race. Suddenly it gets load and very busy, the car in front stalls and I make a quick decision to go to his left, I am in front of a couple of cars somehow but they are advancing rapidly. I turn into the first corner, now in second gear and accelerating past 90mph but still way to slow, as the road straightens out I am passed on both sides just as the first gearbox grinding causes me to back off a tad. Into the hairpin and as I brake I get significant under steer, followed by over steer as I power out onto the back straight, the fastest part of the track. I glance at the speedo passing 130 (forgetting that the low profile tyres drop the real speed by 11%) with the engine at full boar, everything seems to be buzzing, including me.
Then its hard on the brakes for the 90 left at Brooklands, I am not entirely sure where to start breaking and do it to early and slow too much. I get lots of vibration from the front, this is a new feature but doesn’t deter me. I down shift to second and turn in, the shift causes the back end to step out briefly and I hear the tyres chirp. As I turn right through Luffield the corner tightens and the car is in a four wheel drift, at motorway speeds and I am pressed hard into the side of my chair. I apply power and upshift to third into Woodcote, from here I go from the left side of the track to the apex on the right taking me out onto the pit straight, again drifting from the right all the way across the track to the left with the speedo indicating 120mph. At the end of the pit straight its hard on the brakes and a down shift that steps the back out again.
I was starting to catch the car in front when I start getting lapped and I make the mistake of moving off the racing line to let them by, turns out this is a classic novice mistake.
After 7 laps the red flags came out, this is never a good thing. We all slowed and as we came round to the pit straight there were marshals across the track. Three cars reformed on the grid, we believed that the race would be restarted, a few moments later and the marshals indicated we should move into the pit lane, game over.
It turned out that a car that was next to us in the pits had come on to the pit straight and just touched the grass on the left, starting a massive slide. He held it heroically but it spun round the other way and found the concrete pit wall. The car was demolished, even the rear axle was loose
A sober reminder indeed that motorsport is dangerous.
Having said that, the car is amazingly strong, the driver was taken to hospital but only had a sore neck! The safety system fitted are life savers, the seat, harness, roll cage, crash helmet, cut off and fire systems are the most important parts of the race car.
Its also a good reminder of why race cars need to be structurally sound, it is never worth trying to get away with a cheap rusty banger.
The tannoy reminded me to collect my race licence from the stewards office. Smiles greeted me in the office and my licence was retrieved with my first signature on it. They also presented all the competitors with a little souvenir plaque. Wonderful.
Unsurprisingly, my final position was last. My best lap was down to 1:28, four seconds faster than qualifying, and my average speed had risen to the dizzy heights of 65mph!
Well it’s a start. We did this in three months, from daydreaming in a cafe to racing at Silverstone. We did it on a very tight budget and with no special facilities on the driveway, mostly in the rain. I did most of the work on my own but couldn’t have finished it in time without the help of friends like Ron and Franc.
As we packed up for the day, I felt a real sense of achievement. The sun setting over Woodcote corner, the car glinting in the orange light, we made it. OK, we didn’t win anything, this time, but we overcame so many hurdles just to get here.
If nothing else, I can now sit in the pub and bore people by saying ‘ah, yes well of course when I raced a V12 at Silverstone…’
And as for the future, well I need to do better than last, I need a little more from the car and to learn how to overtake. Dangerously, I have a plan, forming in my head….
I had an idea, usually that’s the start of trouble.
I spent my months allowance on another car. It is a 3.6 XJ-S.
Now this is my theory; the new car has the sportspack springs on and a new set of road tyres (which I need desperately), it only cost £400.
I will transfer the front springs, then later I will swap the whole rear axle with its lower 3.54 diff and rear anti roll bar.
This will give the racer more roll stiffness and acceleration, plus a set of new road tyres, which is good.
I will be left with a 3.6 with a ridiculously high diff and soft springs, giving rubbish handling and amazingly good fuel economy. I will then re-sell the car on Ebay as a silly project or spares.
What can possibly go wrong?
I start with just changing the front springs, and after some very interesting experiments with jacks and compressors, I got them on to the racer. They are the same rate as the old ones but drop the front by about 2 inches.
This increases the camber and lowers the centre of graffiti, or something like that, which reduces the roll a bit.
Crucially, it also means I can see more of the road, which might come in handy.
I used bits off the 3.6 to make a solid rubber gearbox mount which brings a little more noise into the cab but holds everything in place exceedingly well.
The 3.6 also donated a few bits of switch gear and ods and sods that needed mending.
I finally got round to ducting cold air from where the inner head lights used to be to the air boxes. I chiselled out the various panels between the head light and the engine bay and used the old 3” ducting (from the interior heater to the rear foot well) to get the air directly into the air boxes.
The old fan cowling had to go, it was restricting the free flow of air, a little bit, and it was rusting and generally getting in the way. It also contained the standard electric fan which is a very old design, i.e. heavy and not very good. To remove it I had to take off the top radiator bleed hoses and lots of wiring.
I became curious about this. There is still a lot of wiring on this car that serves unknown purposes, well, unknown to me anyway. Turns out that the two relays on top of the cowling are for optional headlight washers, which I didn’t have, so I was able to remove them and a substantial bit of wiring.
I also removed the old bonnet release mechanism and various brackets that were no longer needed.
The car handles a little better now and is about 20kg lighter, best have another race.
Donington – a revelation.
I decided to camp at the circuit in a tent on the Saturday night and get the car all ready to go for the morning to avoid the early morning rush that leaves me drained.
This seemed like a good idea at the time.
It turns out that the circuit is directly under the take off flight path from East Midlands airport and they fly all night! Funny old world.
The morning arrived, more or less on schedule and we set about last minute fiddling, checking cold tyre pressures, re checking fluids etc. The smell of early morning fry ups and race car exhaust began to fill the air.
I attended the novice briefing at 8:30 where I met a fellow Devonian racer, Bruce, who runs in the 6cyl Class D. It was good to catch up and we discussed car set ups and the such like. I was informed that the gravel traps were in-escapable and that live recovery was possible (recovering a car whilst the race is still on) due to video surveillance all round the track. This also meant that any transgressions would definitely be picked up on, so a degree of caution was in order.
Sign on was at 9:00 and scrutineering at 9:20, the only comment my chariot received was that the recovery points should ideally be more accessible, the standard recovery points on the XJ-S are on the axles and this would need a degree of excavation in a gravel trap! Possibly an on board shovel..
I had just got back to our camp when the qualifying session was called, which meant I missed breakfast!
Qualifying was eventful, I saw two cars spin and saw more parked at the side of the track. Redgate was claiming many, this is at the end of the pit straight and is deceptively sharp and feels like a skating rink. The art seems to be to turn in late and drift the full width of the track coming out, which is difficult when being overtaken on both sides! Once some space developed I put in a relatively swift lap (for me) then took it easy again to let the brakes cool.
The race was about 4ish, queuing in the assembly area my heart was thumping. Could I actually overtake someone? I knew John was positioned ready to take the best photos of me, as were assorted other friends, all watching with cameras poised. No pressure then.
As we went out for the green flag lap I was looking at the other cars near me, they all had much more experience than me, and my car may be the cheapest on the grid!
We regrouped on the start line. Revs picked up as the red lights on the gantry came on. Heart thumping even more now. The lights go out and there is the roar of 25 Jaguar engines at full throttle, some tyre smoke and cars dart for various opportune gaps,
I accelerate but with the tall diff still in there is a long wait till I am in the power band which lets the car to my right roar past. I see a mass of cars all heading for the hard right hander at motorway speeds, surely they cant all get through? There is a cloud of dust hanging thick in the air where someone must have gone off but the growling throng of cars carries on at full power, I cant see much and back off very slightly which allows the only car behind me through.
Into the legendary Craner curves, the feeling you get going flat out here is awesome. Like a supercharged roller coaster with a V12 soundtrack. I am hooked.
A gap started to develop between the last three cars (with me in my traditional last place) and everyone else. I quickly become aware that I can go faster than the car in front, so now I have to do my first ever overtaking! But where, we are using nearly all the track, sliding through corners. I start to see how he takes corners and got along side him as we go into the blind right hander at coppice, I cant see the apex and I know I am going too fast to be on the inside going in, so I back off.
Coming out of the corner at full throttle on to Starkeys straight I let the engine rev to 6500 before shifting to 3rd and catch up, but I brake way too early for the dogleg onto the start straight.
As we go past the pits again, I know I can go faster than him, the adrenaline is pumping but the fear is still there. I draw alongside into the Craner curves but he takes the racing line and he seems so close that I think we will touch, as he goes into the old hairpin I turn in a little later and carry a touch more speed out on the exit, drawing along side as we slide left up the hill, the engine is screaming in 2nd and I dare not look at the rev counter, I just want to make this stick with all my heart. I get past but now I am going much faster into Mcleans and skid from the apex right across and over the rumble strip on the exit, it all holds together, crikey the car is good. Now I can see a fellow class f driver about two hundred yards ahead. Gulp, lets go for it. I leave braking for the Esses as late as I dare (still way to early though) and the rear wheels momentarily loose traction as I change down to 2nd. I am closing the gap fast as we slide into Redgate, another car has gone off and the view is totally blocked for a moment by dust, I hear gravel smashing into the underside of my car and it squirms under me, then we emerge into craner. I snap at his heals but I just don’t have the talent to overtake. I am pushing him for another two laps and we are both sliding round a lot more, then we start being lapped by the front runners who stream past as if we were parked! I take a tighter line on to Starkeys and draw along side, flat out the cars are matched and we both accelerate to about 110, then some more faster cars come past as we go into the Esses, one of them starts to spin right in front of me and I have an intense second darting from one side to the other trying to predict which way he will go, I squeeze past just in front of his front bumper but have slowed to about 50, the car accelerates (relatively) slowly and my rival is just off my left flank as we dive into Redgate. I am going faster and am totally committed to the line I am taking, any deviation will result in a spin so if he arrives on my inside then we are going off, and at about 80 that will be a long way off. Two faster cars wait till the exit before streaming past and I fly through Craner. With no one in front of be I am battling against my own fear to go faster through each bend, at Starkeys there is a totally clear road ahead, we were so slow that the rest of the pack is half a lap ahead. I press on but when the final lap board is held up with still no one else in sight I ease up and don’t use the brakes again until after the cool down lap and I come into the pits.
What a race, what a circuit. I achieved my goal and overtook two cars. I am exhilarated and tired all at once. Already plans for the next race are forming..
The saga continues with the ‘Black Pearl’ at Snetterton in 2007.
Racing is bloody brilliant, the thrill and excitement of a fierce battle on the circuit, the feeling of achievement, the nomex underwear…
There was a point where I didn’t think I was going to get to the first race of the season, I had to make large repair sections to the underside of the car, many of the ageing bolts on this classic Jag had sheared during the rebuild, the trailer I bought on ebay didn’t turn up, the race tickets didn’t turn up and the day before the race the gearbox developed the ability to engage more than one gear . But we like challenges don’t we?
I put all other work on hold and tackled each problem in turn, and by the day before the race the only problem left was how to get the car to the race. Luckily Dave Ried turned up trumps and lent me his new trailer for the weekend, top bloke.
I got to Snetterton at midnight, pitched my new tent (special offer from the supermarket) and passed out. I awoke at 4am because it was bloody freezing, the cheap tent offered no wind protection and even less insulation, so I took it apart and covered the back of the Disco with it and slept quite comfortably on the back seat instead. Never buy cheap camping equipment.
Glorious sunshine greeted me as I emerged from my nylon and tank tap encrusted retreat on Saturday morning. It was great to meet up with my fellow racers again and swap similar tails of last minuet repairs. Last minuet is one thing, but Crash Gordan trumped us all by actually rebuilding his entire cooling system between races, turning up to a race in a car you haven’t finished building yet is pure class.
The morning started at a rush, Signing on, briefing, scrutineering and qualifying all managed to be timed to overlap, resulting in a significant amount of running and swearing.
Once out queuing up for the qualifying session I had time to relax a bit, but then it occurred to me I couldn’t remember if I had torqued up the wheel nuts, needles to say my first lap was conservative. But after a few laps, gathering pace with nothing major falling off, I started to feel quite happy with the car.
The suspension and final drive mods seemed to work rather well and inspired confidence, my home brewed exhaust sounded commandingly raucous and the engine pulled strongly all the way past about 120mph. Crikey, it felt good.
I am used to qualifying last, but this time managed to have four cars behind me at the start of the first race. As the start lights went out I managed to loose all four places in the first hundred yards. Now I was in familiar territory, but it soon became clear that the car was faster than the one in front which meant it was time to practice the high art of overtaking. Unfortunately I am crap at this, but after dithering on several corners I worked out a safe place to go for it and dived up the inside of the first car, then I remembered to breathe again. The next car was taken on the straight, the new diff proving absolutely spot on as I crept past at about 130mph, whilst all the time my mind was screaming to slow down for the next corner. Another two cars were taken before the end of the race leaving me 22nd out of 28 starters with two cars not finishing.
Gordans old car was driven by Mike Sharman, new to the series, who took off like a thing possessed and won the class 1st rather decisively. So it looks like I had a lot more competition that year and my hopes of getting a few class 2nd s started fading.
The second race was on the Sunday and the grid positions were based on the results of the previous race which meant no less than six cars starting behind me. I was determined to get my start right this time so I talked to the drivers starting around me to get an idea of what to do, Paul Reynolds and Crash Gordan were really helpful and a strategy was hatched.
Sitting on the grid I was still nervous, but when the start lights went out I dived up the outside of two cars in front of me, excellent! Into the first corner surrounded by sliding jaguars, it seemed impossible get that many cars round such a small corner. I conceded the two places to my fellow racers who were much faster, not wishing to slow them up. On the straight I was behind Crash Gordan who is the fastest chap in our class, I figured that if I could just keep up with him then I would learn something. Unfortunately all I learned I s how important it is to prep your car, as his coolant system exploded and covered my windscreen in glycol. The fact that I couldn’t see through it was resolved when I tried to brake and simply went very sideways, sliding on his glycol slick, thus allowing me to see where I was going through the side window.
Setting the suspension up to be progressive paid off as the car waggled through the esses with the casual flair of a drunken tango dancer, but crucially managed to stay on the track. Which was nice. Unfortunately other, faster, racers were not so lucky, have a look at Dave Robbie’s web site for more info.
I made up a couple of places and was sitting 3rd in class again when I rounded the final corner, at the end of the long straight I could see the chequered flag out, but also I could see the 2nd in class chap easing up. It was an opportunity too good to miss so I stayed in second gear and buried the accelerator, I saw the rev counter go into the red, so obviously I stopped looking at it and kept accelerating. I think that if I had to drive the racer home then I wouldn’t have done that, just goes to show that having a trailer is worth seconds on the track. I got six inches in front of him at the finish line and won the first trophy of my life for 2nd in class, the phrase ‘well chuffed’ springs to mind.
There are still mods to be done, however. The diff is cooking due to the inboard brakes. After a cool down lap and a 10 min delay in parc ferme, I measured the rear diff casing temperature at 160 C. That counts as ‘bad’.
Also, when giving it some beans the cooling system couldn’t cope and the temperature started to rocket. On the track I started to use top gear more which helped keep the temp under control but did nothing for my lap times.
I now have a 6 litre XJ40 in pieces in the workshop so the next mod is to get the outboard brakes fitted and see if I can use bits of its cooling system (which is a lot neater than the XJ-S).
I hope to have this all done for Mallory, fingers crossed.
Well that went with a bang! The Mallory race started of with pouring rain, which posed a new challenge as I have never raced in the wet before. But we like challenges don’t we? (am I repeating myself again…)
Cunningly I had plastered the windows with rain repellent and the inside with anti-fog, which worked a treat. Whilst other cars were struggling for visibility and grip, I was merely struggling for grip. I started off very conservatively in practice, feeling my way round and slowly building pace but it very soon became clear by the way the car veered sideways at every opportunity, that there was not much more pace to build. Then it started raining harder.
After lunch, the first races included MR2’s and single seaters, both having substantial ‘offs’ and a number of Toyotas limping back to the pits heavily damaged. This was like an old fashioned warning, a bit like when they used to put severed heads on spikes on the city walls to warn incomers, but without the hygiene issues.
Just before our race was called, the sun came out. In practice I had dropped my tyre pressures to try to get some warmth in, without much success, but now I swiftly set about pumping the tyres up with my nice shiny new high power 12v compressor, the sort that burns your cigarette lighter wiring out, I like over powered motors.
By the way, I now have a race ‘team’ which is a novel experience. Well, I say ‘team’ its only three other people and a ‘sponsor’ but it’s a team to me. I am still used to doing everything myself and haven’t got the hang of delegation yet so they spent most of the time hanging around asking to help, but give it time. We have Nick being race mechanic, Kev being in charge of tents and food, Chris in charge of logistics. My new sponsor is Rik and Lotty who happen to have a vinyl cutter and made me some excellent stickers, they also run a driving school in Birmingham and are very nice people (www.auto-success.co.uk). Right, that’s my part of the bargain done.
Back to the race, it started well enough but the track was still very slippery just off the racing line and as the first overtaking started, so did the graceful ballet of sideways Jags. Going into the esses I was right on the tail of number 47 Paul Reynolds, who is usually the second in class bloke and significantly better than me. A car span in front of us, in a split second Paul had gone to the left and I chose the right but as we passed the stricken car I had a straight run up the hill to the hair pin but Paul was still on the grass. I just got ahead but he was not going to give up easily and went up the inside into the hairpin, I dropped it into first and slid round just in front again then got away cleanly down the hill. My heart was pounding, this was proper racing and as a novice it was quite an experience.
I even started making a little headway, almost getting the hang of it, when a number of cars arrived on the inside just as I went into the big corner at Gerards. There was some tyre squeal, a degree of rotation, a thump and then I was hurtling towards gravel. Now, gravel stops cars and I didn’t want to stop, so I kept my foot in, aimed for the shortest rout across the trap and onto the grass beyond. Now my off road racing paid off as the V12 Jag snaked across the wet grass in a merry salsa back towards the track. But not before Paul had cruised past.
Well, that’s racing. I have to fix the front wing, door, bumper, front and rear suspension on the right and something’s bent in the transmission. Time to take it apart again.
Obviously with the engine and gearbox working well it was time to take them out.
For some stupid reason I got it into my head that fitting the 6 litre V12 from an XJ40 (XJ81) would be a good move because it comes with the 4 speed electric auto box. Needless to say trying to integrate the control systems and wiring with that of an ageing XJ-S proved challenging. Also the gearbox is bigger, needing extensive transmission tunnel modifications and a custom prop shaft. The front of the engine uses a single serpentine drive belt so I had to connect the PAS pump to the existing rack but gut the hydraulic pump that sits behind it to make things work. I also gutted the air con pump to use it as an idler. I saved a few kilos by using the ally XJ40 radiator, which doesn’t fit and required a custom made ally cross member….
Anyway, somehow we got it all running the night before the Silverstone national, but during practice the gearbox ecu slightly caught fire, leaving me with only 3rd gear. Surmising this might make the race a bit tricky I cobbled together a switch arrangement to allow me to choose between 2nd and 3rd. The race started and I leisurely pulled away in 2nd, up to 3rd for the right hander and fairly swiftly the engine hits the rev limiter. Oh dear. So I grab the loose wire that engages 4th and short it against the gear stick, this gives me enough gears to keep up and start making head way again. Unfortunately the broken gearbox ecu seems to have caused the engine ecu to run retarded, the exhaust is so hot that my seat starts to get very warm indeed and I see some degree of smoke in the mirror. OK, ease of a tad then, avoid catching fire, that has to be the best strategy at this point. But the car is still capable of annoying tail enders and we even manage a spot of overtaking.
The reward of all this lunacy is 2nd in class, another fantastic day at the back of the field!
At this point in my racing ‘career’ I took a break, moved house and started writing full time. Just in time for the recession to destroy the magazine industry! So sadly the ‘Pearl had to go.
Luckily it was bought by a singularly excellent enthusiast, Marko Fleming of ‘Rust to Rome’ fame, who has put a manual gearbox in and made it road legal again. It now regularly participates in continental road rallies, sprints and hill climbs.
There was a time when ‘Jaguar’ and ‘V8’ could not be uttered in the same breath, which is odd when you consider the majesty of the Daimler 2.5 and 4.5 V8s used since the ’60s.
But by the end of the ’80s it was becoming clear that the weight of the gorgeous Jaguar
V12 was just too much, plus its enormous physical size was hampering car design, particularly for crash performance where you need some crumple zone rather than solid engine. The engine was revolutionary in the ’70s, but in the ’80s the labour intensive assembly and expensive parts was costing the company more than it was making. For the last years of the XJS the V12 was not even on the official brochures, it was only its legend that was keeping sales alive.
The AJ6 and AJ16 6 cylinder engines were making almost the same power and saved about 120kg which made a huge difference to the cars handling. But even this engine was showing its age.
New shorter engines were needed in order to allow sufficient room for an effective crumple zone. The engines needed to warm up more quickly, for both customer comfort and the ever tightening emissions regulations. This needs more precise cooling in the heads and block plus the use of considerably less metal. The piston ring system needed to control the oil much more accurately and piston friction had to be lowered. Indeed, friction throughout the engine needed to be reduced to meet the fuel economy and emissions targets.
With these issues in mind, a number of alternatives were looked at in the late ’80s, including a V12 derived V6 with the lost power being returned by using a brace of turbos. Another V6, an Orbital 2 stroke engine which gave the same number of power strokes per rev as the old V12 engine, was looked at but oil control and refinement never quite met the targets. They even looked at a number of engines from other companies, which could be bought in without the huge cost of developing their own engine.
During the dreaded BL days there had been some discussion of using the Buick derived Rover V8, which had substantial advantages in terms of weight (in fact it weighed half as much as the V12), cost and size. Unfortunately, most of the advantage came from the fact that it was relatively thin walled and so suffered in refinement a little. But in reality this could have been developed out, as was the case in the final fling of the Rover V8 inside the P38a Range Rovers.
But that venerable V8 was itself a relic of the ’60s and ultimately suffered from the same issues as the old Jaguar engines, in terms of efficiency and emissions. It also struggled to meet the power demands of modern cars, the 4.6 version only putting out 220bhp.
So the bold decision was made to design a completely new Jaguar engine, one that would meet the forthcoming challenges of regulations and customer expectations. Originally code named the AJ12, the project used a single cylinder research engine to examine a number of different combustion chamber, cylinder head/ port and cam options. This data showed that a 500cc cylinder with 26 degree ports and a four valve configuration gave the best economy and performance for Jaguar applications.
Although AJ12 never resulted in a physical engine, the data was used to study a modular engine design concept, concentrating on a 4 litre 8 cylinder and a 3 litre 6cyl, but also looking at a 2 litre 4 cylinder, a 5 litre 10 cylinder and a 6 litre 12 cylinder engine. This would require some rather sophisticated machinery to be able to make all those variants, sharing common components such as piston and valves but little else. As the analysis data grew, it became clear that the complexity of doing all those variants would be crippling, so it was decided to concentrate on 6, 8 and 12 cylinder V engines. Thus the project now became known as AJ26, 26 being the sum of 6, 8 and 12.
But this would be hugely expensive, the fuel bill alone for testing engines runs into millions of pounds per year. At this time Jaguar was privately owned and as such there was simply not enough spare cash to invest in new products. What was needed was an owner who could suffer the financial hit in the long period between investment and return.
When Ford became interested in buying Jaguar, it was only natural to see if one of their many engines would fit the bill. Indeed it was not uncommon for Jaguar owners in the USA to retro fit a Yank V8 so there was some precedence for this already.
But work had already started on the fledgling Jaguar V8 and the Whitley team, lead by Dave Szczupak, were passionate about seeing it through, they had looked at all the requirements and designed something that would give the legendary levels of Jaguar refinement and power whilst being small, light and efficient. But there would be a long road to go, from a concept to a fully customer ready production engine. Typically it takes around 7 years, that’s a long time to ask an investor to wait for a return.
Ford looked at the arguments for both Ford engines and for the new Jaguar engines, after all the data was analysed and the requirements understood, they decided to invest the millions needed by Jaguar to make their own new engine. But this would be dedicated tooling for just the V8, all other variants were not to be.
The first year had been largely given over to defining the requirements, the specifications for each part of the engine such as how much heat goes into the coolant and the oil, how much force is needed to turn the engine over, valve train stiffness, noise levels as well as the major things like the power and torque levels.
This had lead to the basic design, this was put into the new computers and virtual tests run to establish the best coolant flow paths, the best inlet and exhaust port shape, the cam profiles and the such. A huge amount of data was produced and analysed, without making a single engine. Somewhat different to the early days of the V12 when development was a matter of calculated guess work and then lots of test engines trying it all out.
The calculation gave most of the answers, but some elements still required real world testing. To this end some elements of the new engine were experimented on in isolation, using a current production ‘slave’ engine as a base, giving rise to some odd reports in the press of the new engine being based on this that and the other engine. For example, in order to try different bore and stroke combinations on the single cylinder rig, the engineers looked about for existing parts from all sorts of manufacturers, at one point it was using a Peugeot piston and a Mazda con rod!
The first V8 engines were run on test beds in late ’89 and the first car to receive one was an XJ-S, one of the cars that had just finished being used to evaluate the twin turbo AJ16 in fact. As is always the way with the first ever engine installation, nothing fits, mounts, hoses, air intake and exhaust manifolds all had to be fabricated for the job. Steve, one of the mechanics on the job, recalls ‘they gave me a bag full of exhaust tube and various bends and told me to get on with it’. At the end of ’90, after a couple of weeks of trial and error fitting work the first 4 litre V8 Jag burbled into life and was universally admired by the small select audience of management privileged enough to see it, particularly in America which was a crucial market.
It weighed about the same as the old 6 cyl but had more power and a greater spread of torque, thanks to the new variable cam timing system. But there was a small problem, it didn’t sound like a ‘Jaguar’. Although very appealing, the V8 burble sounded like any normal mid size car in the USA and part of the Jaguar magic was the very high levels of refinement and quietness. Sound is such an emotive thing and much debate was had as to what the new engine should sound like, eventually the decision was made to make it quiet and an enormous amount of work went into designing complex intake and exhaust systems. It is interesting to note how this has changed now such that the current XKR even has a device built into the bulkhead to help you hear the engines magnificent growl.
The first car I drove with the new V8 was an XJ40 in about ’93 at the Ford research centre in Dunton, Essex. The car was based on the XJ12 body, code namedXJ81, which had completely new metal work in front of the bulkhead in order to accept a V engine. This car was bristling with new technology, it had one of the first electronic throttle systems and this particular car had a manual gearbox but with an automatic clutch. As you shifted gear the systems would move the throttle and clutch so as to give you smooth gear shifts. It was marvellous to drive but ultimately it was easier to just use one of the excellent ZF 5 speed auto gearboxes instead.
Its interesting to note how Jaguar has had a history of technological innovation, and how right from the start Jaguar was showing Ford new things. In return Ford showed Jaguar how to massively improve production processes, improving quality and reducing costs. This relationship is continuing to this day, I am pleased to say, with both sides benefiting.
As the engine developed, the early tunes were used to check and refine the basic performance and emissions characteristics. Then cars were used to tune the transient response, that is to say how the engine responds to acceleration, deceleration and gear shifts. This is always a very difficult balance between good drivability and good emissions, a slightly rich fuelling on acceleration give very good drivability but will fail emission completely on hydrocarbons alone.
Part of the solution was to ensure the automatic gearbox control system ‘talked’ to the engine control system. This kept the throttle, fuel and spark precisely in tune with the change in engine speed during the shift, allowing the engine to anticipate the changes rather than have to react to them after the fact.
After the engine had received a good stable tune, it was time to test it in all the harsh climates it would face in the real world. Traditionally this involves driving it in the Arctic and in the deserts of Arizona or Africa. But now tests could also be done in Fords climatic test chambers which drastically cuts down the development time and expense. As well as cold and hot climate tests, the new cars had to be tested in extremes of damp to check the corrosion resistance of the components and all the wiring. Then there is the rough road testing, both on specially prepared test track with a range of harsh surfaces, and on shake rigs where computer controlled hydraulic rams try to shake the car to pieces. In short, a lifetime of use and abuse is concentrated into a matter of months. By the end of ’94 a huge amount of data had been produced and all the necessary changes had been made, the results were looking very good indeed.
After this year of climate and durability tests, the final tweaks could be made and then it was time to start running the cars at government approved test centres to get the various certifications needed to sell a new car. At the same time further tests were re-run in house just to confirm that the final version was working as expected.
In parallel to all this development, the production plant was tooling up. First prototype tooling is made and the whole assembly process is tested, any special tools or assembly methods are identified and the first set of workers are trained. The first few test cars were built this way, as were the cars eventually used for the journalists to drive at the launch in ‘95.
The cost of production tooling is huge, the Bridgend AJV8 plant cost Ford £125 million. So it was vital to be certain that everything was right before the orders were placed, this could only happen when all the test data was in and all the tweaks had been tested. This is still true today and is one of the reasons it takes so long to get a new idea into production.
So, in ’96, seven years after the project started, the first XK8s were sold with the all new, entirely Jaguar, V8 engines. A new era had begun.
The original 4.0 litre V8 went through many detail revisions, and endured the dreded Nickasil debarkle that struck many alluminium bored engines of that era. All the lessons learnt were rolled out together in the later 4.2 litre version of the engine, this unit has a reputation for toughness as well as performance and has been raced with some success too. When Land Rover joined the group it was a natural choice to replace the less than reliable BMW V8 with the trusty and powerfull Jaguar unit. In Discovery it was stretched to 4.4 litres in naturally aspirated form but was left at 4.2 for the supercharged variant, 400bhp seemed perfectly sufficient for a Range Rover back then…..
As with all technology in this rapidly changing modern world, eventually it needed a rethink to regain ground lost to competitors who had brought out engines with the latest innovations. The very name ‘Jaguar’ conjures thoughts of tradition and heritage, but it is easy to forget that a fundamental part of that tradition and heritage is innovation; pushing the boundaries back and surprising the car-buying public. In the 70s and 80s, arguably they made the world’s only mass production V12, and at its launch the XJ6 set new standards in refinement and performance coupled with superb looks and all at a very reasonable price. And whatever you may personally think of the XJ-S, it was a very bold move and still has a very strong following.
The all new AJ-V8 GenIII five litre V8 engine demonstrates the continuation of that innovative tradition, capable of delivering over 500 bhp in a selection of very civilised luxurious cars. And as a demonstration of the engine’s strength, a basically standard engine, a tad over-boosted in a slightly modified XF-R was driven at 225.6 mph on the iconic Bonneville salt flats, faster than the XJ220 super car.
It is interesting to draw a comparison with the magnificent old Jaguar V12, intended to provide approximately 20% greater performance than the 4.2 XK six cylinder engine of the time.
In a similar way, the new AJ-V8 5 litre replaces the 4.2 V8, and pushes power levels up by similar amounts; from 420 to 510 bhp for the R version. However, some things are radically different this time round; the new larger engine manages the rather impressive trick of being significantly more economical than the engine it replaces. An astonishing achievement but absolutely essential in today’s, also radically different, environment.
The V12 was also very advanced for a road car engine at the time, in both its concept and manufacture; it was all alloy and designed for fuel injection from the outset, although they were forced to run carburettors temporarily on the E Type. By comparison the new V8 also uses the latest materials and sports an advanced fuel injection system which heavily influenced the engine design, specifically the cylinder heads with a central fuel injector in each combustion chamber.
The injection concept was proved out before any prototypes were made, on a highly modified current production engine taken out to 4.5 litres. The first real prototype engines were created in 2004 and were immediately and relentlessly tested in engine dynamometers, where each engine can be tested in isolation under precisely controlled conditions. Some engines did specific tests such as trying to deliberately foul the spark plugs, or push the performance limits, and others were run on durability cycles designed to stress components to the max, many a time I walked past a test cell where the exhaust manifolds were glowing bright orange as an engine was run at full tilt.
It is of course the people that really make a company, such as the crack team of expert technicians who build and prepare engines ready for testing, often covered with so much complex test equipment that the engine is totally obscured. Or the chaps in the dedicated powertrain machine shop, a small room packed with tools to weld, cut and machine almost any component, often at short notice, using a mix of the ultra new and the traditional techniques that have served Jaguar engine development for many decades. Research by its very nature involves the unforeseen and as a team, their resourcefulness and creativity has saved many a day. It is the talents of dedicated people like this that form the ‘DNA’ of the company.
After initial assessment of the engines, it soon became clear that the naturally aspirated version would meet its performance targets with ease, something that is quite rare in the rest of the car industry, and the supercharged version could exceed expectations without effort so the original power target was raised from 500 to 510 bhp.
The first car I drove with a prototype engine, in 2007, was one of the first engineering ‘hacks’ and so the engine tune was still splendidly raw. It is from this point that skilled engineers start refining the car’s response, making the car do what the driver wants rather than just reacting to crude mechanical inputs. Before work could begin, this particular car had to be driven from Gaydon, where it had been assembled, to Whitley for testing. As I was making that journey myself I volunteered to take the test car, unfortunately it was pouring with rain and as yet there was no traction control – this lead to a few moments of unintentional entertainment and a degree of sideways progress, but even at that embryonic stage it was still a wonderful car to drive.
Indeed it is an essential part of the vehicle’s development to test drive in every type of likely environment so that the design can be finalised before test cars are sent for official emissions certification all over the world. So cars are out and about with disguise kits on years before launch, trying to avoid the hoards of press photographers camped out in the hedges near the factory. Whenever ‘spy shots’ of a new car are printed, it’s standard practice to work out who was driving and then mock them mercilessly, although sometimes it can land the driver in real trouble if more is revealed than is wise.
As ever, refinement is an essential Jaguar characteristic and this has been achieved by ensuring the moving parts are perfectly balanced in the traditional manner, but also with the new Gasoline Direct Injection (GDI) system, where the fuel is forced directly into the combustion chamber at very high pressure. It controls combustion in such a way as to minimise vibration and noise, effectively by shaping the way the cylinder pressure rises, as well as reducing emissions, better fuel economy and higher performance as if the system raises the fuels octane rating. The whole engine is designed round the system and a lot of hard work ensures all the different factors work in harmony, from the computer synchronised high pressure pumps to the crystal operated injectors that give a sequence of perfectly formed fuel pulses.
The technology has near magical control, when you hit the start button the engine will synchronise, analyse the current air and coolant temperature, check the oil level and temperature, check all the sensors are working, set the fuel pressure on the twin double-acting high pressure pumps, check and adjust throttle angle, set all four cam positions, charge up the ignition coils and the 160 volt injector control circuit and be ready to fire the first cylinder within one revolution of the engine.
And it’s not just the engine that makes for a stunning drive; the gearbox is a lighter yet stronger version of the ZF 6 speed which works in a detailed and complex harmony with the engine, exchanging data and requests in a high speed electronic conference. For instance – when changing gear the gearbox asks the engine to adjust power to balance the kinetic energy left in the drive train and so removing any cause for a jolt or surge, it all happens in a fraction of a second, all for your driving pleasure.
It’s all very impressive stuff and a million miles away from the possibilities available nearly 20 years ago when the design of the last V8 started. The sheer volume of work that goes into the new engine merits a celebration: so for the privileged few of you who get to drive one of these wonderful cars, please take a moment to look under the bonnet, a lot has gone into that modest space.
The ‘Supersport(s)’ label is shared between two of the worlds most powerful luxury cars, both Bentley and Jaguar field ultra fast chariots with force fed V engines. But whilst the Bentley is a stripped down version of its much acclaimed two seat Grand Tourer, the Jaguar is a full fat version of its four seater limo. Two very different markets, two very different cars, but one very good excuse to go thrashing fast cars round the fabulous Millbrook test tracks. Oh I’ve gone all misty eyed just thinking about it. But this is no ordinary ‘journo thrashes a fast car’ type article, oh no, there is an angle that may enlighten…
Just walking up to the truly magnificent Bentley Continental GT Supersports is an occasion. As I get closer details start revealing themselves, there are no less than four radiator grilles plus two elongated bonnet vents which all collude to give the impression of a barely contained massive powerhouse under the hood. The huge alloy wheels, polished to within an inch of their lives, do nothing to conceal the equally huge cross drilled brake discs and shiny black callipers with Bentley scripted in elegant white lettering. Everything about it spells power, pure and simple.
Inside is furnished with the obligatory herd of dead cows but with the addition of box quilted fabric inserts in the door cards and seat centres, this combined with the beautifully crafted and very usable knobs and leavers with polished and machined metals gives a feeling of a classic luxury aircraft. Maybe I should have worn a flying jacket for this one.
Firing up the mighty W12 twin turbo engine is disappointingly undramatic, it just starts immediately and settles into a refined hum, surely this sort of machine should burst into life and crackle into a snarling and lumpy idle? OK, maybe that’s just me then. Being primarily a luxury car refinement is still prominent, but as the sporting variant the exhaust has been allowed a bit more freedom, the suspension is a touch firmer, its just over 100kg lighter and generally the driver feels more connected to the road. Which is nice.
Obviously with 630PS on tap from the 6 litre twin turbo W12 performance is brisk, in fact the 0-60 dash takes 3.7 seconds according to the spec sheet, but its delivered in a refined and constant wave of thrust as 800Nm of torque sweeps from a mere 1700rpm up to 5600rpm in an artificially constant level. This smoothness can be a bit deceptive, with the speed flooding in almost unnoticed. The stability control works with the 4×4 drive system delivering 60% of the thrust to the rear and allowing a tantalising amount of over steer drift when powering out of corners.
As an experiment I set it up for a long sweeping corner with a little over steer, then floored the accelerator pedal (can’t call it a throttle pedal any more as it isn’t directly connected to the throttles) to see what happens. Doing this in a 600bhp car a few years ago would have resulted in instant death as the back wheels spin into oblivion and the car pirouettes into the scenery, no such drama with modern cars as the stability control adjusts engine power as well as brake balance (yes it applies the brakes when you accelerate in a corner) left and right to keep the car pointing in what it thinks is the desired direction. All very clever, and essential if you are going to let ordinary members of the public loose in cars with twice the power of an original Countach! That’s why pretty much every modern car has some form of stability control, as an example going back a few years the Sierra Cosworth had a reputation of being a bit to powerful and wild, but that only had 204bhp which is less than an Audi diesel estate. How times have changed. Anyway, back to the Bentley which is still balanced on the power round that long corner…
When pushing hard the body roll is noticeable but controlled, you can feel the weight but it feels much less than the 2240kg that this ‘lightweight’ version of the Continental has. But it’s on the straights that the flying B excels, even on the damp Millbrook test track it rockets forward with unrelenting pace, luckily the massive ceramic brakes haul the speed down with even greater force, a testament to the amazing capabilities of the Pirelli 275/35ZR20 tyres. Interestingly the rear track width has been widened by two inches to improve handling, I say interesting because this now makes both the front and rear track near identical to the standard Jaguar XJ, strangely I never thought of the standard Continental GT as being a narrow car…
The last part of the stunning Millbrook ‘Alpine’ route, which I am sure used to be simply called the ‘Hill’ route before it featured in a James Bond film, is a little jump simulating a hump backed bridge. Actually it is not supposed to be a jump, drivers are supposed to slow down, but as the multitude of sump scars in the tarmac attest temptation to play can be irresistible. Anyway, the Bentley landed with minimal damage and carried on its way, ahem.
As I departed that circuit and drove gently back to the base camp situated in the middle of the complex of tracks and circuits the refined aspect of the car showed through, wafting me through roundabouts and junctions, pulling away on wet concrete T junctions with absolutely no drama, all in all a very usable and impressive car indeed. In another decade it would have been called a supercar, but in this moment it is just a blindingly fast big GT with epic presence.
Stepping from the glitz of the Bentley, the stylish Jaguar feels almost minimalist with that wonderful thin sweeping arc of dark wood traversing the dash and door tops, and just two air vents to break up the lines, with the digital dash sunk deep into the binnacle.
But here’s the thing; it is because I was just in the Bentley that the Jag looks Spartan, if I had just been driving a ‘normal’ car would it feel as empty?
And this is a crucial point, everything is relative, particularly in something as subjective as a road test. It’s all about reference points, it’s all very well for a motoring hack like me to go swanning around in super-fast luxo cars all day and say one has slightly better on the limit handling, but this is meaningless to anyone who doesn’t drive these cars on private test tracks.
So for this group test I brought in a bit of a wild card, possibly a joker, but in any case a dose of normality. The third car in this group test is the very capable Skoda Superb, the estate version, with a 1.6 diesel.
Now at this point you might think I have lost the plot, and obviously you might have a good point, but bare with me and hopefully things will start to make sense. No guarantees though.
Back to the Jaguar XJ Supersport, a totally different type of car to the Bentley with a full set of luxo seats and four zone climate control. The ‘sports’ aspect comes from the optional active differential and the supercharged 5.0 V8 engine. Pressing the start button breathes life into the surprisingly ecological recycled aluminium block, indeed it is amongst the smallest of the big engines (such as the Mercedes 6.3, the above mentioned Bentley 6.0 etc.) but punches well above its weight. Again this is a trend we will see more and more of, where manufacturers use smaller engines with more boost to deliver even higher performance levels than their older big engines, the VW Tsi uses a 1.4 to give 170bhp as an example.
Refinement is a Jaguar speciality and the car effortlessly glides away, as the speed rises the only thing that spoils the ride is the low profile tyres, a problem that infects far too many cars these days.
But the Mr Nice-guy pretence is dropped as soon as the big Jag hits the test track, flooring the loud pedal engages warp drive which turns the swooping hill roads into a high speed roller coaster and the engine note is transformed into a gruff roar by the exhaust muffler bypass valves and a very cunning device that brings a subtle sample of the superb intake noise into the cabin.
In gear acceleration on a real road feels very similar to the Bentley, the 6 speed gearbox has very swift and precise shifts (both cars use the same ZF 6 speed box) but going fast into corners the Jag seems to carry more speed with less roll and greater composure. This is not surprising when you consider that this short wheel base XJ (still a foot longer than the Bentley) weighs in at 1892Kg, that’s over 300kg less than the Bentley despite being bigger with more seats and toys.
There are two reasons for this massive weight difference, first is Jaguar’s use of an aluminium shell, a technology they first used with on the old XJ and refined on the XK. Many manufacturers have looked at ally shells and of course Audi use them on some cars, but production challenges make it a much more expensive process and requires a lot of specialist knowledge to get right. On premium cars manufacturers can sometimes pass on the extra cost, but for mid range cars it is still not commercially viable which is probably why Jaguar still use a steel shell for their XF.
But the world is changing, and now fuel consumption (and therefore CO2 emission) is under scrutiny. This may tip the balance in favour of ally shells, just look at the CO2 figures for the Bentley (388g/km) and the Jaguar (289g/km), that’s a huge difference. As laws come in that will set ever tightening limits on CO2 even supercar manufacturers will have to take action.
The second reason for the weight difference is because the Bentley has four wheel drive, so has an extra transfer box, front prop shaft, front diff and half shafts. You might be thinking that this is unnecessary baggage for a GT car, but consider this: much of Canada, Russia, Scandinavia and the new markets in China spend a fair chunk of the year covered in snow where a rear wheel drive car will struggle to get off the drive way, they also have a lot of new rich who want a car they can be seen out in, you do the maths. Right, back to the track.
It’s remarkable how similar two very different cars can feel when being thrashed round a track, both have more than enough grunt to power up the very steep twisty hills of Millbrook and fling the occupants over the crest at break neck speed. But pulling away at that damp concrete T junction in the Jag highlights the big advantage the Bentley has with its 4WD, the rear wheel drive Jaguar limits wheel spin as it maximises grip from just two wheels, and whilst there is no drama pulling away there is also less acceleration. I suspect this is why there is such a big difference in the 0-60 times with Bentley smashing it in 3.7 seconds and the Jaguar smartly stepping forward in 4.7.
Both these cars are quick, in slightly different ways, but how quick are they in real terms? And for that matter how quick is quick anyway? To find out I drove exactly the same route in the Skoda estate diesel. The first thing I notice is the noise, the estate is very good for noise in its class, but having just complained about road noise from the Supersports low profile tyres I take it all back compared to the road noise at motorway speeds from a normal car.
As I head onto the first section of track I accelerate, but nothing happens. Two things are worth noting, firstly in all three cars I started this bit at about 70mph, in a normal car flooring the accelerator at 70 will obviously result in only mild acceleration, but when you have become accustomed to the Bentley or Jaguar you automatically expect neck snapping acceleration at this speed. Secondly this section of road is up hill, in the other two cars I hadn’t even noticed it was up hill, in the normal car I am considering changing down just to keep the speed up.
After a few tight corners to get the tyres up to temperature I hit the long left hander, in the other two cars I went in slow, about 60mph, and powered out to asses how they handled hard acceleration in corners. In the normal car I struggled to get it round at all at 60mph, let alone accelerate. It was in fact a fairly tight corner, but the big cars just grabbed hold and got on with it in a way that a normal car could never do.
Through the twisty bits I had noticed the Bentley had a bit of body roll, at a lower speed in the normal car changing direction mid corner resulted in a lurch rather than roll and enough tilt to worry about scraping the mirrors in the road, turns out that ‘bit of body roll’ was actually blooming impressive at that speed, and the fact that the Jag had even less turns out to be stunning. Again, totally different worlds.
Then there is the ability to be pushed hard all day, the hill route is relatively short, just a few miles, so the big cars had barely warmed up by the time it was over. By contrast the normal car was loosing power (modern diesels wind the power down when the intercooler or oil gets hot to preserve longevity) and the brakes just started to fade. This is no bad reflection on the car, no one in their right mind would drive a 1.6 diesel estate that hard for any length of time, it’s just silly and on anything other than a private test track it’s suicidal.
I think it’s important to get a sense of perspective, in order to better understand what is being looked at, I learned a lot about the Jaguar and Bentley by driving a Skoda Estate. Skoda also very kindly let me loose in their rather excellent VRS which is undoubtedly a fast car, in a different class of performance to the normal estate car, but again several classes behind the big boys.
All this goes to show the effectiveness of the Bentley and Jaguar suspension, brakes, control system, engine and transmissions. And indeed that of any of the very high performance cars about these days. There is a lot more engineering in one of those, and when I see the price tag the size of a house I can’t help but think that actually that’s not bad value. These cars are not just good, they are amazing.
The Jaguar V12 engine is one of the greatest iconic powerplants ever made, powering the E Type, XJ12 and XJ-S models plus numerous successful race cars from Touring Cars to LeMans GTs. But for some the apparent complexity makes it a very scary option. Having raced these magnificent units I feel it’s time to set the record straight.
The first time I opened the bonnet on my XJ-S V12 I just stared at it in disbelief for a few minuets, then gently shut the bonnet again and walked away. To say it was full would be an understatement, it looked like someone had emptied a very large bucket of automotive spaghetti into the engine bay until it was full, then smoothed it off with a very big oily trowel.
Which is a very great shame, because the engine itself is a fairly straight forward design, just with 12 of everything. Owning and driving one is a fantastic pleasure, round town the engine is silent from within the cabin and it is arguably more refined than a Rolls. On the open road it has a briskness that defies its size, and given enough space has a relentless thrust that just keeps on going.
So if you have a desire to own one then don’t let the tales of woe put you off. It is only that the parts bolted on to the engine, such as the fuel system, air control system and electrics that seem shockingly complex, and that is only until you get the hang of what does what.
The good news is that the engine itself is very reliable and can cope with a huge amount of abuse, the bad news is that because of this many older cars have many missed services, giving the new owner quite a lot to do. The base engine has gone through three main changes over the years; the original E Type and XJ engine had flat cylinder heads and is the one preferred by the racing fraternity, but it had an alarming thirst for fuel. The fuel crisis of the 70’s led to the High Efficiency HE engine, introduced in the early 80’s, with a very high compression ratio and very special combustion chambers with a heavily recessed intake valve for very high swirl rates, this limits tuning potential slightly but gives amazingly reasonable fuel consumption, I used to achieve about 25mpg on a run from my XJ-S HE. The HE stayed in production into the 90’s when it was replaced by the 6 litre bock which was largely the same but with a longer stroke.
All these engines are very robust, as they are derived from the XJ13 race engine the 5.3 revs to 6500rpm and the 6 litre goes to 6000rpm. Because they are designed to be quite happy running at these speeds, in an every day road car they are totally unstressed. Of course this pedigree means it is still great for classic racing today, many racers take engines straight out of scrap cars and merely change the oil before heading for the track.
Speaking of oil, it does take quite a lot of the slippery stuff, over 10 litres is usual making an oil change a substantial investment. The oil tends to last quite well however, an oil cooler is standard and the engine’s quick warm up system minimises oil contamination. When changing the oil it is best done with warm oil, as with most engines, but leave the exhaust for a while to cool down because the oil filter is right next to the down pipes and contact is inevitable.
The simplest incarnation was in the carburettor fed E Type and XJ12 models, but the engine was designed for fuel injection from the start, and as soon as a suitable system was available it was fitted to the XJ12, the XJ-S was injected from the start. The systems was very sophisticated with little extra features to enhance performance and emissions, all stacked on top of the engine, making it look so complicated. Breaking it down a bit, there are six main systems in that spaghetti; fuel, vacuum, engine management, ignition, cooling system and air con.
I will take a typical S3 XJ12 as an example, then go over differences on other models later. Opening the bonnet reveals a network of small bore tubing, some of this is the fuel system with the U shaped fuel rail feeding all 12 injectors, but most of the small tubing is the complex vacuum operated control system for the distributor. The front of the engine is dominated by the air con pump with its cylindrical silencer, yes that’s right the air con pump has a silencer, very refined.
You will also notice it has two cooling system pressure caps, one at the front of the engine and one on the expansion bottle on the wing. Nearer the rear of the engine is the throttle pedastle, this is where the throttle cable operates a circular device that in turn operates the two throttle links, more of that later.
Lets start with a potted history of the ignition system, it has gone through several major changes over the years, most models of the 70’s and 80’s use the 12 cylinder Lucas Opus distributor, similar to many other BL cars of the time. The HE engine’s high compression ratio required much more spark energy at high speed than the older engines, and feeding a spark to 12 cylinders at engine speeds up to 6500rpm require the coil to store a lot of energy, it was too big a job for just one coil back in those days so the cunning chaps at Jaguar doubled up the coils, one coil has the king lead to the dizzy and the other sharing only the low tension 12v side of things. This secondary coil looks a bit odd, as the king lead post is blocked off, the main coil is located next to the dizzy but the secondary coil is mounted right at the front of the car, in front of the radiator, if its faulty or missing then the engine will misfire at high rpm but may well run perfectly round town.
Later models managed to use just one, more modern, coil. But when computerized mapped ignition was installed the need to have the coil towers further apart required a novel system from Mirelli which effectively incorporated two 6 cylinder distributors in one, stacked one on top of the other in the same housing. This system has two coils next to the distributor and two king leads feeding a split level rotor arm.
The final iteration of the V12 ignition saga happened after the change to 6 litres when the distributor was deleted in the and replaced with individual coils for each cylinder.
Of these systems the most common is the Opus, and it is also the one with the most complicated vacuum advance system ever made. Its also very clever. To get the best from an engine the ignition advance must adapt to all engine operating conditions, a simple vacuum advance system is a big compromise but back in the 70’s full computer controlled mapped ignition was not an option for mass production. So the vacuum capsule is connected to several air solenoids, a vacuum regulator, a vacuum dump valve. The biggest problem with this comes from old rubber hoses perishing, the second biggest problem comes from people re-assembling the system incorrectly. One of the clever things the system does is warm the engine up quickly, and its huge amount of coolant. The ignition is retarded when cold and extra air is let in via an air solenoid, this is controlled by its own little electronic box of tricks which has been known to go wrong resulting in lost power and idle problems, but when it works it works very well. To compensate for lost power when running so retarded extra air is let into the manifolds by yet another solenoid. It is possible to remove this system completely, the only down side being longer warm up times.
One of the popular horror stories about this engine is that the spark plugs are impossible to change without a major engine strip down. Well, in fact most of them are no problem at all, but the front two are very close to the air con pump, a special tool is recommended but another option is to undo the pump belt and mountings and ease it over, without damaging the hoses, to get enough access.
Because of this difficulty it is quite common for the plugs to be left in far too long and start to corrode in place, so its worth blowing all the dirt out of the plug recess and allowing some penetrating oil to soak in before attempting removal. In fact it is quite important to blow any detritus out of the way first, the plugs are ate the top of the engine and it is easy for debris to accidentally fall down the hole during the change. Make sure you get the right plugs too, there was a change of design to taper seats when the HE engine came in.
The electrical system design also laughs in the face of convention. The fuel injection control really was cutting edge and in some ways daring. The early, pre-HE, ECU was relatively simple but very good at its job, the HE ECU is more sophisticated and has a manifold pressure sensor built in to the box. Unusually the ECU is mounted in the boot and the wiring for the injectors and sensors passes through the rear bulkhead and takes a tortuous route through the interior and finally emerges through the front bulkhead from whence it sprawls over the engine and wing edges to meet the control relays mounted on top of the radiator. The HE system also has a vacuum hose from the intake manifold going all the way back to the ECU. Obviously there is the potential for older cars wiring or vacuum hose to have expired in some way. Electrical connections are prone to corrosion which can usually be removed reasonably easily, but sometimes it works out easier to fit new connectors. The vacuum hose is worth replacing if its older than a decade.
The throttles, one on each intake manifold for injected engines and four on carb versions, are operated via a centrally mounted disc which is pulled round against a spring by the throttle cable, this disc also operates the load cable for the auto box and the cruse control, it also has a switch on some models for the auto box kick down and the throttle potentiometer for the ECU. So all in all its a complicated part, but all you usually need to do to it is check that the throttles all start to open at the same point, if they are a little out of balance the engine might only be using half its cylinders as you cruse round town, luckily its a simple operation involving undoing the lock nuts and winding the links in or out as described in the service manual.
The fuel system is quite remarkable too; on the XJ-S there is a fuel pump in the boot sitting in its own little tank, fed by gravity from the main tank. On XJ12 there are two main fuel tanks which both feed the fuel pump in the boot but with fuel solenoids to select which tank is used. The excess fuel returns from the engine to the tank, but because the fuel picks up so much heat in the massive engine bay it goes through a small cylindrical fuel cooler that is plumbed into the air con return pipe.
Early systems suffered from hot re-start problems due to having very small bore fuel rails which are prone to fuel vaporisation in the heat, the later larger bore system is a useful upgrade. When the returning fuel gets to the tank it goes into a pipe in the main tank which in turn goes back into the pump tank, that way returning fuel is mainly pumped straight back to the engine and the main fuel tank temperature doesn’t rise too much. This is all done to stop fuel evaporating, which became part of the emissions regulations in the 70’s, instead of the tank just venting to the atmosphere it vents into a can, tucked up into the right hand buttress on XJ-Ss and one on each rear pillar on XJ12s, which allows the vapour to condense and return back to the tank via yet another small bore pipe, determined gases are allowed to escape via a restricted pipe on the top of the canister which goes to the engine intake.
Needless to say its a very complicated system and is prone to problems, one of which is a strong smell of fuel in the cabin. Some owners rip the whole vent system out and replace it with conventional vent pipes.
Later models supplement this vent system with a carbon canister in the engine bay which absorbs fuel vapour and is emptied into the engine intake during part throttle running, ensuring the vapour is burnt and never vented to atmosphere. This is controlled by the engine ECU via a solenoid in the pipe from the canister to the intake.
Although all this pipework looks intimidating initially, all you really need to do is keep the hoses in good order, and if you are so inclined the system can be simplified and most of the plumbing removed.
The cooling system is another stunning work of art. Each cylinder head has an externally mounted coolant manifold with a thermostat and top hose at the end, in the E Type both top hoses go forward to the radiator, which was the traditional sort with a tank at the top and the bottom and the cores running vertically so the two top hoses went straight into the top tank, relatively simple compared to what happened next.
On XJ models it got a lot more complicated, a more modern radiator with horizontal flow and a separate expansion tank is used for greater efficiency and lower bonnet lines, and with a tank ate each side it made connecting the two top hoses a bit more tricky. The solution was to put a baffle plate one third of the way down the left hand tank, effectively splitting the radiator in two. The left top hose goes to the top of the left tank and the coolant then flows across the top third of the radiator into the right hand tank where it is joined by the right hand top hose. Then the mixed coolant from both heads goes back to the lower left hand tank via the lower two thirds of the radiator. Still keeping up? The bottom hose is attached slightly above the bottom of the lower left hand tank, and then feeds back into the water pump.
To make this set up work a small bore hose connects the top of the radiator to the expansion tank, mounted at the side of the engine bay. This tank feeds back to the radiator via a bigger hose at the bottom. It also supports one of the hoses for the interior heater, the other coming from the back of the right hand cylinder head coolant manifold. At the top of the tank is a pressure cap, but because this is not the lowest point in the system it should not be used to check the coolant level.
Amazingly it gets more complicated, between the two thermostat housings is a balancing tube which supports a second pressure cap, it is here that you should check the coolant level.
If you make the mistake of opening both pressure caps then coolant will drain from the top of the engine into the expansion tank and spill out. The highest point in the system is the interior heater matrix, so when refilling the coolant after a change it is best to have the front of the car raised a bit. You wont be able to get all the coolant in in one go, the trick is to run the engine with the heating on full and give it a few revs briefly then switch off and magically you can get the rest in.
Bizarrely the standard service schedule specifies dropping two pots of Barrs leaks with every coolant change, probably due the the huge number of joints in the system. This can lead to clogging in some of the coolant galleries and the interior heater matrix, so a good flushing can be helpful, and as ever old rubber hoses should be renewed every ten years or so.
Although this set up is genuinely complicated, all that is needed is normal maintenance such as coolant changes and checking for leaks, so don’t let it scare you off.
The front of the engine sports four belts on most models, and again although it looks complicated it really isn’t. at the back is the alternator belt, tensioned by moving the alternator, then there air con drive belt which is tensioned by a high mounted idler pulley, next we find the belt that drives the water pump and power steering pump tensioned by moving the PAS pump, lastly there is a fan belt with its own little tensioner pulley.
So there you have it, a glorious engine hidden under a complicated dressing. Although there are many neglected examples around, with some careful attention going through each system a stage at a time will ensure many happy years of sheer motoring joy.