Computer crash

When I was little I remember listening to old people talking about a time when there where no cars, the feeling of excitement and wonder when they saw their firs one, a feeling mixed with a little fear as the mechanical marvel seemed to take over every aspect of life. Where once they played in the road now the car was king, and a ruthless one at that. Communities divided by a constant steam of deadly traffic.
Of course today we take the car for granted. Many have moved away from the workers slums into suburbia and now rely on the car to support this freedom.

ASL, DSC and other stability control systems allow even the clumsiest driver to enjoy supercar power in reletive safety. Technology can be amazing.

We teach our children ‘road sense’ so they can cross the road safely. Most drivers are not deadly speed demons (although in town most people still speed, 40 in a 30 zone IS deadly). Society adjusts and we move on.
Now it seems that its my turn to sound old because I remember a time when there were no PCs.
I remember the excitement of my first Sinclair ZX80, the awe of seeing the colour ZX Spectrum.
But now I feel the fear.
Now don’t get me wrong here, I am a great believer in the usefulness of computers, I have a degree in computer systems engineering, I have made a career out of devising and tweaking computer control systems for cars.
The performance of this Lamborghini is only possible because of the massed computer systems doing highly complex things to make the engine, gearbox, suspension and brakes work to perfection.

But still, now I feel the fear.
When I was studying to become and engineer, every step of the way I was told of the importance of doing things properly. With a large computer program one has to exactly and correctly specify what it should do in every detail. One must also specify what it must not do! Once the program is written then it must be tested against this specification and every possible combination of circumstances must be tested. That way there are no ‘bugs’ and unexpected effects.
But life is not like that.
The software (and also hardware now) on almost everything is so complex that it requires a computer program just to be able to test it.
No one programmer can do the whole thing, its just too big, so we have teams. So now we have programs to help the teams work together without bits getting left out and prevent miss interpretations etc.
But we live in a capitalist society. Its not just the engineers that create products, its corporations. Many individuals with their own beliefs on how things should be done dictating the boundaries and detail of what the engineer can do but without a sound understanding of the technicalities.
Money has too be made (exceptions include Linux (three cheers)) and so whole chunks of code from other programs are grafted in to new programs, the people producing this new program may not know the details of how this chunk was written and all its effects. Sometimes there may be a ‘surprise’ effect caused by the interaction of this chunk with the rest of the program, other chunks grafted in or indeed other programs running on the same machine or network.
Testing takes time and money and delays the launch date. Some things just cant be tested completely due to their nature, for example if your program predicts the weather then how do you test every possible combination of weather across the whole world and still meet the deadlines.
The Jaguar CX-75 uses complex computers to manage a highly tuned engine plus high power electric motors to bring stunning performance with minimal fuel use, a fantastic use of technology.

Also the hardware too is so complex that it is not commercially viable to test everything, or indeed possible. With several million transistors on a single chip is never going to get tested for the effects of every combination of individual transistor failures.
So that’s where we are today. Our systems are only partially tested and often a patchwork of other peoples work all stuck together with hope and optimism. Or indeed sometimes cynicism.
Many consumer products are made by inexperienced teams and pushed out by unscrupulous corporations (particularly in countries where software standards are not enforced) and are largely unproven.
Many of us have experienced the result of this growing problem, such as the PC just locking up when you try a new program or simply getting slower and slower as time goes by. These bug and software faults are so common that many people think it is normal for computers to behave like this. For instance the PC I am writing this on is twelve years old, it still does everything it was designed to and since running Linux it hasn’t slowed right down or ground to a halt, yet still most people accept that computers need replacing every other year and expect it to slow down over time. It must be realised that it doesn’t have to be this way, technically, but commercial pressures will continue to make the problem worse and this will be compounded as more and more code is piled on to bring use ever more features.
Complexity is a big problem and is the subject of many a professors career, things are getting more and more complex and there is no proper engineering control on it.
Now, the reason that I am writing this is not just to have a good whinge about my computer crashing or indeed to complain about commercial forces ruining good engineering. Those things make me angry, but they are not the cause of my fear.
The fear stems from how we are using these systems as a society, how we are relying on the unreliable.
Computer systems are now increasingly being used as part of the law enforcement system, finance control, travel systems and even food production
Speed cameras always cause a good argument so I will stir thing up a bit further. Now I know very well that excessive speed increases danger of injury and general twisting of machinery and putting a speed camera outside a school is no bad thing.
The issue for me comes from the fact that the picture generates an automatic fine for a person. There is no human judgement in the loop, bang, guilty until proven innocent. And that’s wrong.
A friend of mine suffered from a theft from his car, not the usual sort of theft, the number plates were stolen. It turns out that persons of criminal persuasion are stealing a car then cruising round till they find an identical type of car and putting those plate on theirs. Then they can generate speeding fines and parking tickets with impunity and even commit serious crime knowing full well that the system will point the finger at some one else. It even cause the police to waste time with the wrong chap, keeping the heat off the criminals long enough for them to make their escape.
Guilty until proven innocent, trial by computer, not good, not very British.
Maybe soon we will all have ID cards. This means that criminals only need to forge one item instead of a string off items as at present, thus making their life easier. The systems used for security are simply to complex to be testable, and driven down on price so the quality is marginal. Its simply not reliable.
If you want quality you have to pay for it because quality systems take more time to engineer and more time to test and it all costs money.
We are entering the beginning of a time when cars become more autonomous, adaptive cruise control will adjust the car speed to the traffic conditions, lane assist can nudge the steering to stop you drifting off your chosen path, we even have auto parking systems. It is a logical step to bring all these ideas together and link them to the sat nav to create fully autonomous cars, Google are investing heavily in this idea. Once the systems become common there will be increasing pressure to ban manual driving, after all an autonomous car doesn’t get road rage, doesn’t speed, can see through fog, never gets distracted and should never crash. All those computer systems running all those programs written by thousands of different people at different times in different places and controlling your car….
In the near future there will be an attempt to make remote vehicle arrestors mandatory on all new cars. This system uses ABS systems that have full authority breaking and engine management systems to bring a car to a halt using a radio command that only police will have. In a simplistic world this is great, you report your car stolen and the police can bring it to a halt when the conditions are safe. No more getaway cars. Well, unless criminals use older cars, but that loophole is easily solved by making classic cars illegal and crushing them all!
The problems include accidental stopping of the car (you cant prove the software completely due to its complexity and you cant prove the hardware completely because you cant test every failure and every type of possible radio interference etc), incorrect use by the police or other agencies, vehicle being stopped by criminals equipped with illicit stopping systems for the purpose of car jacking. Finally there is always a way to bypass the system, always a loop hole, a bug, a back door or an ‘unintentional feature’.
I was on a train in Germany last year which suddenly stopped in the middle of no where without warning, brakes full on. Luckily I had finished my coffee so the cup was empty when it slid of the table. The cause of this potentially dangerous emergency stop was a software error in the very system that is supposed to protect the train from crashes.
Our corporate based society does not allow for well written systems to be made as profitably as the quickly written ones.
This is a real problem and is getting worse as more systems are used.
In my life I rely on a mobile phone, I rely on my car, my computer, email, bank direct debits, automatic payments, alarm clock, microwave, fridge, washing machine, traffic lights etc. The power feeding my home is controlled by systems all linked together in a network. The amount of chlorine in the water I drink is monitored electronically. Aeroplanes are flown expertly by computers over my head, the air traffic is controlled by other computers.
I use my switch card to pay for car tax, the little computer in the post office reads my details and talks to one of many networked computers at the bank, the figure in my account file is reduced and a message sent to the post office bank computer to tell it to increase the number in its account. Then a message is sent to a computer at DVLA and it changes the value of a variable in a file so that when another program does its daily check of who has tax it will not automatically send a message to another computer to send me a fine and automatically turn me into a criminal. I never see these computers and they never see me. But they can bankrupt me accidentally or send me to jail.
These systems are not designed completely by engineers, the specifications and design constraints are created by politicians and computer sales executives who simply don’t understand.
When I was a child, I was proud to be British, a country that believed in tolerance, understanding and fair play. I was proud of my country.
Now I am scared of my country and the automatic systems that rule my life.
My bank local branch has just got rid of all its cashiers, you have to use the machines now. Signatures have been replaced with PINs.
Make no mistake, these systems give us great ability as a society and as in individual. The principles of the systems are very good, it’s often empowering and can change lives for the better. Even this blog site gives me a platform to express my beliefs and concerns in a way that was impossible a generation ago. I am a great believer in technology.
But as far as I can see if we are to rely on systems then they must be reliable.
Also, there must always be a human in the loop when ever civil liberty is at stake.
And finally, there must always be a manual back up for those odd days when thing don’t quite work the way they should.

The truth about electric cars

Or at least the truth from an engineering perspective. And that is an important distinction because of course the main catalyst for the change is political, there may be some very fine environmental and technical reasons for the change too, but politics holds all the aces. It can make oil prices prohibitive, it can subsidise new technologies that herald breakthrough innovations.
You see, every life changing new technology had to start somewhere, it usually starts off prohibitively expensive and a bit unreliable. Just think about those early mobile phones the size of a suitcase with a battery life of only a few minuets and call costs a hundred times greater than a normal land line. Or even the first computers, the size of a large room and less brains than a digital watch. The format is well established; pour loads of funding into research, laugh at boffins making experimental machines with questionable ability, wait for a company to spot the potential, get it into production and within ten years every competitor is developing better versions.

Rolls Royce are leading the charge (pardon the pun) in ultra luxury electric vehicles.

But electric cars are a bit of an exception because at the dawn of motoring they were a front runner, even Porche’s first car was electric. 130 years ago petrol was not readily available, you bought it in cans for quite a lot of money, car journeys were very short and cars were so expensive that only those with a large estate could afford one. Electric cars had the advantage over those first fledgling petrol cars in many ways, they were faster, quieter, much more reliable and had no starting problems. They didn’t even need a gearbox or clutch mechanism, so driving them was a far simpler affair than a crash box piston powered chariot.
But the materials technology needed to advance battery design was simply not there, the early EV hit a performance limit that it couldn’t break free from. The second problem was in motor control, all they had was switches, and as motors became more powerful the need for fine control at low speed became more problematic.
By comparison funding poured into petrol engine design, at that time it was far easier to improve than electric cars and oil companies were understandably keen to see this new product thrive. A couple of world wars forced engine design ahead very rapidly, not least to power aircraft from the humble Tiger Moth to the magnificent Spitfire.
Very rapidly it became far easier to make a high power, low cost petrol engine, opening up the possibility of cheap mass market motor cars.
Electric vehicles didn’t stand a chance. Half a century ago there was simply no reason to invest in electric vehicle research, emissions concerns had not yet manifested, climate change was unheard of and oil supplies were plentiful. A few enthusiasts continued to attempt to make electric vehicles, enjoying their simplicity and quietness, but materials technology would still limit their capability.
But times change, and now with political difficulties in oil supply, a far greater and ever developing understanding of emissions problems and climate change, coupled with massive advancements in technology there is an overwhelming desire to find alternatives to petrol and diesel.
This means that funding is now pouring into research in electric vehicles. But as mentioned above this is merely the first stage in a product becoming a commercial success, early adopters such as Honda with the Insight and more recently Toyota with the Prius have been suffering the commercial pain of subsidising less than ideal technology, but remember this is another essential stage in a technology’s development.
I hope that gives you an idea of where we are; about half way to getting a really useful, cheap and effective electric vehicle. There is now sufficient funding from a sufficiently large range of institutions, governments and corporations that the rest of the development process is pretty much inevitable, after all they all want to see a return on their investments.
Of course electric cars are not the only option for reducing CO2, existing piston engines could be re-engineered to run on hydrogen, and that fuel could be obtained by electrolysis of water. Storing hydrogen is a bit tricky unfortunately, but there are some exciting new developments that could make it a viable option. This has the advantage of using existing engine technology, but introduces large inefficiencies due to the process of hydrogen manufacture, its transport and the low efficiency of the internal combustion engine. You’d be lucky to turn 15% of the electrical energy used in hydrogen production into energy at the car’s wheels. and as ever you loose all that energy as soon as you apply the brakes.
The observant amongst you will know that lost energy from braking could be recovered by hooking up generators to the wheels and using the recovered energy to power the wheels on the next acceleration, as in KERS and other regenerative brake systems, but then you are carrying part of the weight and financial burden of the electric car but without all the benefit.
When you consider the total path from the source to the wheel the electric car can work out significantly better, potentially getting 50% of the source energy to the car wheels.
The other interesting possibility is gaining some, or possibly all, of the electricity from solar cells built into the car body. Various companies are developing composite body panels and special paints that act as solar panels that can be unobtrusively incorporated into the car design. In the UK the average energy from the sun through our legendary gloomy cloud is enough to power a small family car for about ten miles each day, so if all the car does is the school run and weekly shop then there could potentially be no fuel cost. Although as ever with new technology the first cars to have this feature will be hideously expensive and totally negate this benefit, but in time it will become a viable option.
Emissions are not the only reason for going electric, as the technology matures and becomes cheaper it will eventually become far cheaper to make an electric car than a combustion engined one. On a modern small car the engine and associated emissions systems can easily cost more than the rest of the entire car, getting this cost down is a huge incentive to car companies that struggle to make a profit at the best of times. in fact car companies have been trying to get up into electric cars for decades, remember the Ford Think?
There are many other benefits too, electric drives lend themselves to the ever increasing demands of advanced traction and stability control systems. As driver aids such as auto parking gradually evolve into fully autonomous self driving cars, having a simple method of accurately controlling the torque at each wheel becomes increasingly important.
When you put all these factors together the case for electric vehicles becomes compelling, and when you add in the political desire to reduce dependence on unstable oil producing countries the argument becomes overwhelming.
Obviously we are not quite there yet, historically the big problem has always been the battery. Old methods resulted in heavy, expensive and physically large units with limited range, they haven’t really changed in over a century. But in the last ten years or so there has been renewed investment, finally, and whilst there is still a long way to go we are definitely on the road to success already.
In fact as the ‘power density’ of batteries improves, eventually it will exceed that of petrol. This means that eventually electric cars will be lighter for the same power when compared to a petrol or diesel car, or more interesting to a racer like me, an electric car will be more powerful for the same weight. Imagine massively powerful electric supercars with precise control of the torque at each wheel from its four wheel motors, the ultimate in performance. The future world of electric vehicles is a very exciting place.
So there it is, electric cars offer huge benefits to the environment, car companies, drivers and world politics. They are not perfect yet, but within a decade or two they will be as ubiquitous as mobile phones.
And yes, before you ask, I still prefer the sound of a V8. But as long as the car accelerates as if it had one then maybe I could cope, after all we can always simulate the sound!

For more news about electric cars why not follow Robert Llewellyn, a superb ambassador for the EV revolution:bobbyllew

And you must follow Jonny Smith and his fabulous drag racing electric car ‘Flux Capacitor’: Carpervert

How to spot a car company that is about to fail.

The car industry is a very spacial environment, with some very special people in. It seem to attract an amazing mix of personalities and a huge range of talents. Making cars fires some people with an enthusiasm that drives them far beyond the limits of their own talent, it’s a curios business, not quite like any other area of industry.

Old MGs are fun, but they were constrained to use parts that were already out of date, this one has a Lancia Twin Cam engine and shows what could have been.

The history of the car industry is littered with the corpses of dead dreams, idealists, optimists, dreamers have all had a hand in making the story, but equally so have rogues, villains and cheats. It’s even more colourful than the newspaper industry!

Sometimes it’s just one name that signifies the loss of hope, the crushing of dreams and the tragic culling of ordinary hard working decent folk’s jobs. Names like Delorean are well known, but he is unusual in being almost universally held guilty, more often opinion is ferociously split. Names like Eagan, one camp see him as securing the future of Jaguar

The Rover 400, a good example of using Honda's platform investment and adding their own identity. Trouble is it was never replaced when it had run it's course, just facelifted, twice.

with a wealthy parent (Ford), others view his skill in presenting a failing company as being a raging success as nothing more than a traditional used car salesman, some love him, some hate him, this is more often the case with the main characters in the industry.

There are a couple of key facts that are far too often overlooked when bloated executives prepare a new daring business plan for a car company. Firstly it takes a hell of a lot of money, time and people to develop a good car. I think the Ford Focus cost something like four billion dollars, seven years and a couple of thousand people to develop. That’s a huge investment, and a really long wait for a return, remember that is four billion over seven years and not one salable car produced, it would be many years after production started before any return on investment was made. In the Focus case it turned out rather well, but that’s not guaranteed, remember the Scorpio? That was designed many years before launch, as are all cars, can you predict what cars will look like in five years? Can you make a style that will fit in nicely on the high street in ten years time? It’s really easy to poke fun at the tragedy of the Scorpio, a car that lost Ford the D sector market so utterly that they found it more cost effective to just buy Volvo instead of trying to resurrect it, but when you look at the Mercedes that came out a few years later it looks very similar so they were not that far off.

Car design is a massive gamble, huge in fact. Not only does the product have to meet all the customers expectations, but it must meet incredibly stringent legal requirements too. I won’t bang on about the incredible scale and breadth of technical challenges, suffices to say it makes rocket science seem easy by comparison. I’m struggling to thing of another high tech, multi computer controlled, real time systems that has to function in specific ways even whilst being crashed.

It’s a sad fact that throughout the history of car design incompetent management have made the tragic mistake of thinking that the technical things they don’t know about must be easy. Just look at the once magnificent Rover K series engine, originally designed with a closed deck block, no head gasket worries there, solid and robust. But a decision was made to stretch it to a capacity well above it’s original design limits, this is not an engineers decision, this is a managers decision. This decision necessitated the loss of the closed deck and the inevitable sensitivity of the head gasket, but the mangers did what they so often do and pushed it through. Then they had a the clever idea of saving money by making the smaller engines in the same way, thus making the formally robust 1.4 just as fragile as the 1.8. The rest is history.

This is just one example of management not understanding the importance of investing in new designs to meet new targets. This problem is often scaled up to include whole companies, not just one car part. Trying to produce a new model without the correct investment in time, money and people results in inadequate products. Inadequate products result in reduced sales, and so less revenue coming in. Now a clever management team would spot this and invest in a new product to get sales up again, this is a long term strategy and makes successful companies. But a poor management team will notice the falling revenue and react the wrong way by tightening spending, reducing investment and continuing to bang out inadequate cars but with shinier badges and brighter paint.

The Rover 75 was a great new car. By 2003 the company should have started work on it's replacement so that it would be ready for launch in 2010, but they didn't.

When BMW sold Rover they had already made the investment in the 75, from that point on not one new model was developed. The Phoenix chaps made no obvious attempt to replace the old Honda derived 400/45/MGZwhateverthehellitwas etc. Remember it costs billions to develop a new car, they ‘invested’ millions, so no new platforms, no new engines, no new sales. From the moment they announced their plans most people inside the industry knew it was just a matter of time before the company sputtered to a tragic and unnecessary halt. The fact the the government also were convinced to invest millions into the failing company merely shows that ministers were either clueless or had other motives for handing over money to the increasingly wealthy board members.

The new Jaguar XJ. Real investment leads to real success.

Compare this with Jaguar, a company that had suffered inadequate investment since the grim days of the ’70s. When Ford took stock of what they bought and found out the truth they swallowed hard and started investing in making new models such as the XK8 and the S type, they also invested heavily on a complete redesign of the XJ plus they funded the development of Jaguars own legendary V8 even though Ford had a wealth of V8 engines available. They invested heavily and sales increased. No one is perfect and the idea that the X type would out sell the BMW 3 series was flawed, that decision cost them dearly. And the conservative styling of the S type and the XJ limited appeal. But again they saw struggling revenues and invested in new models, the current stunning XJ, XF and XKR were all funded by Ford. They bought Land Rover when BMW split up the Rover group and used the Jaguar engines in a range of new models there too. Unfortunately for Ford their own cash flow problems meant they had to sell Jaguar Land Rover before they saw the return on the investment, but their decision to invest in new engineering has resulted in Jaguar Land Rover posting billion dollar profits.

The Bentley GT was a totally new design, VW invested properly in the factory, the people and the product. A big change compared to the previous owners.

The same success from investment can be seen at companies such as Rolls Royce and Bentley. Morgan is a fascinating departure from the norm, they have steadfastly remained focused on doing what they do best, on servicing their unique customers demands, resisting the brainless call to expand excessively. They have stayed small but crucially stayed profitable, it is a very clever model and one that any aspiring business leader should make time to understand. But even they have understood the need to invest in new models, but where they could not afford to design their own parts they have bought in parts that meet their needs, benefiting from someone else’s investment and avoiding the trap of under investing in designing their own engines etc.

Focused investment at the right level generates success. Under investment generates failure.

So you see, if a mainstream car company announces it is going to make new models then there needs to be a large amount of money behind it to work, billions not millions. It also need the facilities and people to make it happen, thousands, not hundreds.

If you see a company that historically designs only one new model at a time then they will have the facilities and people to do only that. If they announce that they will suddenly make five new models at once then they will need five times more people, larger facilities and huge investment.

It is sad to see that there are such companies about in the UK, making bold plans but with a fraction of the required investment. The same old story, with inevitably the same old ending; lots of trouble, usually serious.

How to make an old Jag fast.

I have had a lot of questions about setting up old Jags for race and track day action, so here are a few answers for those that feel the need to experience the glory of a V12 on track.


The starting point, an eBay XJ-S V12...

The same basic principals apply to both XJ-S and XJ6/12 cars. First up which car to go for.

The V12 in 5.3 form is fantastic on the race track with a 6500rpm rev limit and over 300bhp readily available, although the standard cooling system is dire. The first V12s had flat cylinder heads and can be tuned up to over 600bhp (at great expense), later models had the High Efficiency HE heads which limit power but drastically improve fuel ‘economy’ and is still good for well over 400bhp. Early cars had a 4 speed manual gearbox as an option but these are hideously expensive, most have the immensely tough GM TH400 auto box which can also make a good race box when fitted with American drag racing parts. I raced an auto with manual override and it was superb. The last XJS cars had the 6 litre V12 with a 4 speed 4L80E auto which can be modified to work in manual mode either mechanically or electrically (paddle shift style), but these cars are rather expensive.

The 6 cylinder engines in the XJ-S were either the AJ6 in 3.6 or 4.0 forms or the four valve AJ16 version of the 4.0. All are powerful with over 300 bhp quite feasible. Available with either the 5 speed manual or the 4 speed ZF auto, again the auto can be modified for racing but the manual is a simpler option.

The final version, it had a 6.0 litre V12 and an extra gear to play with.

TWR offered a manual version available through the official Jaguar dealer network, this used the Getrag 260 gearbox as found on larger BMWs of that era, but as the gearbox has an integral bellhousing you will need an adaptor plate to fit a non-v12 sourced box.


Basic track mods:

Brake pads, race brake fluid, jack the bonnet open an inch and fit good tyres. Give it a full service and off you go!


The more complicated version:

All cheap cars are rotten, so plan for welding. The front subframe which holds the engine up and holds the suspension on rusts from the middle out, good second hand ones are over £250 and quite a big job to change, so make sure you get a good one. The smaller cross member under the radiator also rots out but can easily be replaced with a strip of suitable metal and is not a deal breaker.

The office, and a very nice place to be when doing 150mph down the back straight at Silverstone.

The front of the sills rots behind the ally splash guard but is reasonably simple to repair. The back of the sills is a very complex construction and includes the rear axle radius arm mount, this is a sod to rebuild but for racing it can be simpler to just cut the whole lot out and weld in a simple sill and convert the radius arms to a ‘cotton reel’ bushed rod that is mounted into a fabricated box intruding into the rear passenger foot well. This mod cuts out some weight too and also improves axle location.

When viewing a car pull up the rear seat base, rain water leaks in from the quarter light seals and pool in the seat base/ inner sill area. The race car solution to a rusty bottom is to cut out the set base and weld a simple plate over it. Also check the front foot wells where water from leaking screen seals can pool and rot the floor. Many cars have been undersealed which is unhelpful as the rot starts from the inside of the car and the underseal can hide it from inspection.

The Jaguar V12 remains one of the best engines ever made, and the noise at full throttle with a race exhaust....

Mechanically the cars are strong, but bushes, bearings and ball joints wear. For racing I replace bushes with polyurethane and budget for new bearings and ball joints. Brakes get extremely hot so we use BNS grease in the wheel bearings which copes with the heat. The gearbox mounting is a cunning and complex unit which will be worn and make clonking noises when driving hard but can be replaced with a simpler rubber mount. The steering rack has very soft bushing so fitting pollybushes sharpens up the steering considerably, some cheapskate racers just limit movement on the bushes by simply putting tie wraps round the bush edges!

The cooling system on V12s is dire, I flushed the accumulate rubbish out then fitted coolant made of about 1% water wetter, 10% anti-freeze and 89% water which has better heat transfer ability. Then I removed the visco fan and associated heavy bracketry, the fan cowling and the original electric fan. I fitted a large electric fan instead as the fan is only needed in the pits. Jacking the bonnet open an inch lets the hot air out which is just as important as letting cold air in.

Keeping it simple, SportsPack springs off a 6 cyl XJ-S, Gaz race dampers, rcae brake pads and race brake fluid. Job Done!

The brakes fade horribly on track, I used EBC Yellow Stuff race pads and Motul RBF600 brake fluid. The fluid is vital, it has a higher boiling point but has to be changed more regularly. To get a bit more cooling air round the rear inboard brakes I took the access plates out of the boot and removed the boot seal to let the hot air out, another approach is to cur the boot floor out completely which further improves cooling and makes access much easier to the rear axle as well as saving weight.

Weight loss is key, the sound deadening is everywhere and it is a good days work ripping it out. A tar based substance is glued onto the floor and has to be chiselled off. The interior heater system is very heavy and can be largely thrown away, although leaving the drivers side screen fan helps demisting. I used RainX anti-fog on all the glass to prevent misting, much lighter solution than a heater. The standard XJ-S seats only weigh 7kg so make a good cheapskate racers choice. Door lock solenoids can be junked to save 2kg, but the door cards weigh naff all so leave them in. I would also leave the electric mirrors on as they are less than 1kg each and work very well.

The centre exhaust silencer can be replaced with a straight through tube for a few more bhp and less weight. The standard intake airbox is a little restrictive and the trumpet can be cut off and a larger hole formed with a radiused edge, it is vital to get cold air to this and running ducting from the headlight surround works well. The middle headlights on quad light models can be removed to make an excellent cold air intake point, although some bodywork has to be cut out to get into the engine bay. The standard paper air filters work well when new, no need for expensive sponge filters.

Racing is in the blood, you either understand or else there is no point trying to explain!

The engine oil needs to be able to cope with high speeds and temperatures, I used Castrol RS which is now superseded by Castrol Edge. The other fluids have to be changed for quality higher performance versions too, including power steering, gearbox and differential.

All XJ-Ss had and LSD as standard, the 6 pot models had the lower 3.54:1 ratio needed for racing and is a straight swap to replace the overly high V12 item.

With the car lighter it will sit stupidly heigh on its springs. Eibarch make a suitable race springs but they are pricey. I cheated slightly by using the Jaguar ‘Sports Pack’ springs from a 3.6 model on my V12 which worked out just right. Adjustable front dampers are a handy mod and can be tweaked to suit different circuits – hard for flat ones like Silverstone and softer for less even ones such as Croft.

Fitting 50 profile tyres on standard wheels drops the gearing a tad more and lowers the car a bit too. Buffing the tread down to 4mm will stop them going off due to heat build up, this maintains grip levels and actually improves wear rate. I used Toyo Proxes T1R tyres as they were mandated by the race series, and they seemed to work well even in heavy summer rain.

You may wonder about roll cages, but if the car is ever used on the road I would avoid them because of the injury risk from hitting a steel bar next to your head in a collision. Cages work well when the driver is secured in a race seat with a race harness and wearing a crash helmet. The Jags are strong cars anyway so a heavy cage is of questionable benefit unless racing.

Go on, search eBay now, you know you want to! 😉

All that remains is to fit a race harness to hold you steady and a race steering wheel to speed up response and it’s time to head for the track to have more fun than is decent.


Check out these web sites which I have found very useful:


Winter tyres – the truth

If you don’t have winter tyres this winter you may be wondering what all the fuss is about, and hopefully when you open the curtains in the morning to find a few inches of snow you will very sensibly leave the car at home.

Ordinary tyres are a mixture of many different substances including rubber, carbon black, silicon, sulphur and the steel or kevlar reinforcing wire. The best tyres may actually have over a hundred different substances in, and the exact blend and cooking method can produce a range of tyres with very different abilities.

This summer tyre has wide tread blocks that don't move much.

Ordinary tyres, sometimes referred to as summer tyres, are engineered to work well when hot, to last a long time and provide good dry grip. The rubber based tread compound in summer tyres is relatively hard and the tread blocks are relatively shallow and broad so they remain stable when pushed hard round corners etc.

By comparison a winter tyres is made of a much softer compound which grips the road even when cold. If you run your hand over the tread of a tyre on a cold day a winter tyre will still feel rubbery but a summer tyre will feel harder, more like wood.

But also the tread pattern is very different, the winter tyre will have deeper and narrower tread block, each with a multitude of deep cuts moulded in. This allows the tread to move about very easily and mould itself to the irregularities of the road, allowing it to grip even on ice.

The winter tyre has very flexable tread.

But there is more to tread wobbliness than that, rubber tread grips my moulding itself in to the road surface at a microscopic level, almost flowing over the tiny irregularities of the road surface and grabbing hold of them. But it takes time for the rubber to move into position, only a tiny fraction of a second, but whilst it is taking hold it needs to be almost stationary. Any slipping will prevent it taking hold properly and you get drastically reduced grip, that’s why wheel spin needs to be avoided.

The tread allows this to happen by moving very slightly with respect to the tyre body (carcass), allowing the rubber in contact with the road to remain stationary as the wheel moves above it.

In fact if you look at a graph of wheel slip against the amount of drive force actually being transmitted to the road you see a peak at about 3% on a summer tyre as the force makes the wheel turn slightly faster than the road beneath it whilst the tread is constantly moving back and forth as it passes through the contact patch. But as more throttle is applied and the slip increases it suddenly gets to a point where the tread movement can’t keep up, it starts sliding across the road and never has time to flow into the road surface, and then grip drops rapidly.

There’s a lot going on in that tyre of yours.

So the softer tread compound coupled with the wobblier tread block pattern gives a winter tyre much more time to get a really good grip of the road.

Of course there is a down side to this, the wobblier tread means the car can drift more when pushed hard as the tread blocks almost ‘walk’ across the road surface, you’re not actually skidding but you’re not going exactly where the steering is pointing either. This also means that a winter tyre used in the summer will give worse stopping distances too, in fact a winter tyre starts to let the side down when temperatures go above 10°C and stopping distances can increase by 5%.

The other thing is that the softer rubber would wear down faster in the summer, although modern winter tyres are a lot better than designs from a few years ago. But interestingly at temperatures below the critical 7°C a winter tyre will actually wear down less than a summer tyre because the tread slips less.

In fact 7°C is a very important temperature, it is where a traditional summer compound undergoes a structural change at the microscopic level, the long rubber molecule chains start to lock together, hence it feeling more like wood at low temperatures. This means the tread surface can’t move and doesn’t have time to flow into the road surface as the tyre scrubs across the road when cornering, accelerating or braking.

So below this critical temperatures the grip from a summer tyre starts to drop rapidly, as the rubber hardens it needs longer to grip but the hardening tread blocs actually reduce the time available in the contact patch. Everything starts to conspire against it.

At extremely low temperatures the tyre can become brittle, I have seen customers enjoying luxury cars in northern Russia reporting tyres shattering below -40°C as they pull away.

By comparison winter tyres still work acceptably well at -40°C, which is the standard low temperature the whole car industry tests their cars at. But even winter tyres will eventually become hard as the temperature drops even further.

My Bargain Banger not getting stuck, very pleasing.

So on a day where the temperature is struggling to get above freezing a winter tyre will out perform a summer tyre by quite a large margin, but even at 5°C there is a noticeable difference, Continental Tyres claim a 7% improvement on a wet road. But when there is snow and ice on the road the winter tyre design works well and the summer tyre looses most of its grip completely, making pulling away on gentle slopes almost impossible and generating entertaining video clips for the news channels.

On the continent it is common to have two sets of wheels for your every day car, new car dealers will store your other set for a nominal fee, usually about 50 Euros so you don’t need to find the storage space at home. This is something we are starting to see in the UK now too. Many people run smaller wheels with higher profile winter tyres to allow even greater flexibility and resilience to pot holes and uneven chunks of ice. This also means your nice shiny summer wheels don’t get covered in road salt and chipped by grit. When buying a second hand car it is easy to pick up a spare set of wheels for your winter tyres to go on, often the smallest wheels offered for your type of car are sold on cheaply as owners upgrade to bigger wheels. When storing winter tyres over the summer it is important to keep them out of sunlight which hardens the rubber and prematurely ages them.

Some people may be tempted to just by two winter tyres, particularly for front wheel drive cars. In the snow and ice having a set of winters on the front of a front wheel drive saloon will make the world of difference, both for pulling away and for stopping. As more of the weight is over the front, which drives and steers the car, the vast majority of the traction is needed right there. At low speeds in such conditions some might argue that the back just needs to follow the front to some extent and so winter tyres are less critical, however nothings ever quite that simple.

When you get to clear stretches of road, having substantially lower grip at the back could get you into trouble, most notably if you have to slow or stop suddenly on any sort of band where the back could drift out. On older cars it would be worse as the rears could lock up and, worst case scenario, send the car into a spin, but as yours has ABS it wont actually let the rears lock up but could still run wide. Obviously this all depends on exactly how ropey your old tyres are, low tread depth and aged hard rubber make things much worse.

For this reason the only ‘safe’ way is to do all four, although having two winter tyres is better than none.

Putting two winter tyres on the back of a rear wheel drive car is much more dangerous, it would then have the ability to pull away on very slippery surfaces but have very poor steering and braking ability due to the summer tyres on the front. It could pull away, accelerate, get to a corner and plough straight on into a ditch. Even on rear wheel drive cars front wheel traction is vital.

But what about four wheel drive cars, do they need winter tyres too? If we assume the 4WD car is on new full tread summer tyres and the other car is FWD with equally new winters on, then the winner when pulling away depends hugely on conditions. On a typical compacted snow/ice British winter road the summer tyres will have very little traction and the 4WD may struggle, but these are precisely the conditions that the winter tyres were designed for and the FWD car will probably get away quicker. But if we throw in some fairly thick slush with tarmac or gravel underneath then the fact that both axles on the 4WD are digging through it may tip the advantage it’s way, the FWD having the extra burden of dragging its back axle through the wedge of clag. In this case a RWD car on winters would suffer even more as the front axle has to be pushed through a bigger wedge than the rear.

But driving is so much more than just the ability to pull away, and once on the move the advantage tips decidedly towards the 2 wheel drive car on winters, every other aspect of traction relies on all four wheels and when cornering or braking the car wearing winters will have a clear advantage.

The example I frequently quote is a Quatro I saw pulling out of an icy T junction last year, four wheel spin and a bit of snaking and it got up to speed, tried to turn right and fell straight in a ditch.

Of course the Quatro on winter tyres would be quite a different storey.

Well that’s enough theory, I tried a set of modestly priced winter tyres from Goodgrip, a Scandinavian company that has just set up in the UK and is used to dealing with tyres for extreme conditions. The Hankook ‘Winter i*cept’ tyres are at the lower end of the price spectrum so I can’t be accused of cheating by buying an exotic tyre. These went on to my trusty Bargain Banger Rover 75, so again no cheating by using advanced stability control etc.

After fitting them we proceeded to experience one of the warmest Christmases on record, but this was in itself a good test and at temperatures a shade above 10°C the winter tyres clearly drifted in corners more than summer tyres, but nothing alarming. It should be born in mind that I was testing the tyres, deliberately pushing them hard and putting them in the most demanding circumstances and I feel that someone driving ‘normally’ wouldn’t even notice this extra drift tendency. Unless of course they had to do an emergency stop, that 5% increase in slip means at motorway speeds the stopping distance increases by approximately one car length, from 20 to 21. So although it’s worse it is by no means catastrophic, even so I would rather use summer tyres in the summer.

More recently we have enjoyed snow, ice and temperatures below -6°C, including a few days where the snow partially melted, froze overnight into sheet ice and had fresh snow over it in the morning.

Traction on icy roads is very impressive.

The winter tyres worked very well, pulling away easily up hill with four inches of snow on top of ice. In fact the snow seemed to help with grip on the ice, bare sheet ice has a smoother surface and presented more of a challenge, but even here the winter tyres were very good. Of course applying too much power or going to fast round a corner will still result in a skid, but as the limit of traction is encountered the winter tyres started to break away more gradually and maintained at least some control of the vehicle.

Their ability was highlighted to me by a colleague who commented that a particular corner we had both driven was very slippery and he nearly lost control, where as I had driven round it as normal with absolutely no problems.

So clearly for every day driving in low temperatures the winter tyre is definitely safer and well worth the expense.

There are some other things worth mentioning too, firstly the softer compound gives a quieter and slightly softer ride. Secondly I got very slightly better fuel consumption. At low temperatures the car will use more fuel anyway for a multitude of reasons, but as a direct comparison on the same route driven in the same conditions (between -2°C and +5°C) the winter tyres on my car averaged about 3% better economy, probably because at these temperatures the summer tyres slip more.

I do a high mileage so this saves me about £2 a week and may save £30 over the winter which offsets the cost of the tyres slightly, a full set for my car was just over £200.

So in summery for an investment of effectively £170 I have a car that is still usable in the winter, much safer to drive, slightly more relaxing and removes that anxiety drivers feel when watching the weather forecast.

I think that is a small price to pay.

As an experiment, and to answer many of your questions, last year I ran a set of winter tyres all year. I do a fairly high mileage, usually about 700 miles a week, and usually I drive reasonably hard, so it was going to be a good test.
The first thing to note is the grip on a warm dry day is very modest, they don’t so much slip as glide when driven hard, drifting deeper in corners. It’s all very progressive an easy to control, and of course if you drive a bit slower you may never notice this trait. But of course emergency manoeuvring and emergency stops will also be less sharp.
By comparison, when I bought the car originally it had some nasty budget summer tyres on, fairly new, but the Hancook iCept winter tyres were better than the budget summer tyres even in the dry. Budget tyres are usually worse at pretty much everything.
So basically the winter tyre was perfectly usable in the summer, not as good as a summer tyre but not as bad as the cheapest budget tyre.
However, the soft compound did wear at a noticeably higher rate. Interestingly the tyre tread area became concave, the centre wearing twice as fast as the edges. This is because the softer compound allows the centre of the tyre to centrifuge out at high speeds, and as I do a lot of motorway mileage it basically took the middle out fairly rapidly. The tyre started with about 10mm tread depth all over, after just over 20 thousand miles and eight months the edges were down to about 4mm and the centre was about 2mm.

See how the tread is now concave, even thought this high mileage winter ran at the correct pressure.

So, in conclusion, if you do less than 10 thousand miles a year and don’t drive like a man possessed then a good quality winter tyre could last a couple of years. For everyone else it is better to store the winters in the garage during the summer. Or alternatively use good all season tyres (an experiment I have just started with Goodyear 4 Seasons from Goodgrip), or indeed stay at home for the few days a year when the roads are covered in ice.
I also did some experiments fitting winter tyres to the front and leaving summer tyres on the back, a lot of people asked me about this sort of set up so I thought I better try it for myself. I tried braking mid corner in the worst winter conditions which should be the worst case scenario for this set up, and although the back did drift slightly further out than normal it was nothing dramatic. This was on a Rover 75 which is longer with a lower relative centre of gravity than some of the cars that are sighted as having problems, such as a Fiat Panda, with just two winters on. I think that this may be because the relative lack of rear grip on ice affects the shorter and taller cars more. So although on my test car it worked fine, it does seem to depend on what sort of car is used, it will also depend on the design of the non-winter tyres fitted on the back, mine had good tread depth and large radial grooves which may have helped. So I cannot recommend this format universally, and considering a good winter tyre for an average family car costs less than a full tank of fuel I think it is false economy to only kit out one axle with winter tyres.
In summary, winter tyres – still love ’em.

Sterling Engines

One of the great problems with a conventional car engine is that most of the fuel’s energy gets thrown away through the exhaust (about 30%) and radiator (another 30%ish), in fact your car engine is lucky to extract 33% of the energy from the fuel, and that’s only at full load, at low loads your petrol engine will be below 10% efficient! So wouldn’t it be great if there was a way of trapping all that heat energy and getting more out of it.

I like this design, purely because it's weird!


Enter stage left the Sterling engine, invented by an eccentric Scottish vicar in 1823 and now used in many combined heat and power systems for large buildings.

The name is now applied to a whole range of ‘hot air’ engines – the idea is that you have two pistons and cylinders that are connected in some way. A hot cylinder heats up the gas inside it, causing expansion, the gas is then pumped to a cold cylinder and contracts, thus pulling that piston up. As the heat energy can be totally used up by the engine, in theory it could be 100% efficient. Sounds simple doesn’t it.

Small Sterling engines have been made that work on a temperature difference of only a few degrees, so holding it in the palm of your hand makes it work! The trouble is that they are not very powerful for their size because you need a lot of surface area to transfer the heat energy into the working gas in the cylinders. This gas, often helium because of its excellent heat transfer ability, is trapped permanently in the engine. The more gas you have the more energy can be pumped round, improving efficiency, but this requires high gas pressures and very good piston seals which has been the downfall of some optimistic designs over the years.

Because the fuel is burnt outside the cylinders, this is called an external combustion engine, same as steam engines. And as the combustion is continuous, there is very little noise, almost silent. And they can work on pretty much any fuel, petrol, diesel, coal, chip fat or even junk mail.

It’s unfortunate that in practice, complete heat transfer never happens so the total fuel efficiency ends up being only 10% better than a conventional internal combustion engine. But the main benefit comes when the two types of engine are used together, the exhaust and coolant from the internal combustion engine being used to run the Sterling engine, together extracting up to 70% of the fuel’s energy. Obviously this ends up being a big, complicated heavy lump, but that hasn’t stopped people putting it into cars.

A simple version of a Sterling engine has two cylinders driven 90º apart, one cylinder is heated up and the other is cold. The two cylinders are filled with your working gas, possibly helium, and joined by a big tube which contains a regenerator. That is a posh word for a sort of radiator, or heat exchanger, that keeps the heat on the hot side of the engine and the chill on the cold side, this is a very important part and has a massive effect on the engine’s efficiency, a good one will recover 95% of the heat energy.

You may be surprised to hear that one of the most successful Sterling engines was made by Phillips, better known as purveyors of electric shavers and expensive tellys. The Dutch company of boffins started on the design in 1938 but were delayed by an inconvenient world war. The work lead to a very nice portable generator set that enjoyed modest sales success, but the focus of my ramblings this month is the 4 cylinder engine, based on their work and made by United Sterling of Sweden, that was fitted to a Ford Pinto in 1974. The V4X31 used base engine parts from the Saab V4 and was the first car to be driven directly by a Sterling engine. It produced 115bhp at only 3500rpm and worked at about 40% efficiency.

The V4X31 was an early insight for Ford who were working with Philips on a 4 cylinder 170 bhp swash plate engine, that’s where the crank is replaced by a tilted disk, as each piston rod pushes down on the disk; pushing it round in a circle.

Cunningly, in both these engines, they managed to get both the hot and cold cylinders in the same bore, the lower piston having a hole in the middle for the con rod of the top piston. At this point you really need to look at my hastily crayoned diagram, because I am now going to say ‘rhomboid drive’!

Apart from being a great phrase to baffle the pub expert with, rhomboid drive is the way they managed to get both con rods to move up and down with absolutely no side movement, essential when one con rod goes through the middle of a piston, hopefully without any gas leaking out of the hole.

The system uses two cranks in parallel which are geared together at the bell housing end of the block. Each piston has a fixed con rod dropping down to a joint where two articulated con rods are attached, one going to each crank. Who ever thought that one up probably didn’t get out much.

To stop the gas leaking out, which was nitrogen at 150 Bar, the piston seals were nylon sleeves that rolled up and down, a little like rolling nylon stockings down, funny lot the Dutch. It also had the added benefit of having virtually no friction.


Of course the home mechanic could possibly try constructing a simple sterling engine by converting a V twin bike engine to run with one cylinder being heated from the coolant or exhaust from a conventional engine, the other cylinder being water cooled. You could remove the valves from the heads and connect both inlet ports together with the pipe containing the regenerator, which could be an old intercooler cut down, and something similar nailed on to the exhaust ports too. Then belt drive it onto the conventional engine’s front pulley.

It wouldn’t be light but on something like an old Range Rover it could bring the fuel economy up to diesel levels and deliver something like another 50bhp for free. Which is nice.

Tales from the workshop

It has been another eventful year, as some of you may know this year I took the difficult decision to close my workshop, so this is a slightly self indulgent look at the last three years projects that have been through the ‘big shed’.

The Black Pearl, a mind of its own and frequently holled.

The first occupant when I moved from my old workshop in Coventry was my beloved Jaguar XJ-S V12 race car. You might think racing a V12 is a bit opulent, but it was one of those things that I really wanted to have done, even if it turned out to be just one race. The car itself took a fair amount of work but having bought a sound ebay car for £1500 it only cost a further £1500 to get all the bits to make it into a race car, so that’s a V12 on the starting grid at Silverstone for 3 grand, which I think is a bargain. As it turned out I did three years racing and even slipped in a bigger 6 litre V12, I sold it last year and it is now back as a road/track day car in Scotland.

Motorway speed accross forrest tracks, ditches and rivers. Rallying is to easy, Comp Safari is where the real fun is!

Next in the shop was my long suffering Comp Safari racer, if you don’t know what that is then I strongly recommend you Youtube ‘Comp Safari’ and be prepared to be amazed. I built this car using my old Range Rover as a base, then bought lots of nice bent tubes and fibreglass bodywork from Tomcat Motorsport, Comp Safari racing is intense and punishes the car massively, it is both a technical and a physical challenge, this car is now running somewhere down south with its new owner as a road and play day car.

My toys were swiftly followed by the first customer project, this Volvo C303 6×6 army ambulance from the ’60s had the Volvo straight 6 petrol carb engine and a four speed box, oddly enough the fuel consumption was horrific. The customer wanted it as an expedition vehicle he could live in, so I raised the roof by just over a foot. Then I fitted the 2.5 Tdi

A Volvo 6x6 is the perfect party bus.

diesel engine and 5 speed gearbox from a Land Rover Discovery, which really doesn’t fit! After modifying the turbo, the manifolds, removing the water pump and fitting a remote electric pump, moving the alternator, shortening the bell housing, making new drive shafts, designing a new gear selector system, converting cable clutch to hydraulic, moving the brake servos, raising the cab, making new bodywork over the engine…… oh loads of stuff, did I mention it really didn’t fit? Anyway, it now works, has an MOT and is somewhere between Coventry and Africa.

The donor for the Volvo was a 300Tdi Discovery, bought for 500 quid with two months MOT left, it was a classic rot box and would never get through another test, ideal really.

Why did Land Rover never do a Discovery pick up? So usefull, like a Defender but comfy and bigger.

Whilst I was modifying the body of the Volvo I tried a few ideas out on the Disco including a quick pick-up conversion (about an hour with an 8 inch angle grinder), I quite liked it and it was used on the farm for a few weeks before its engine was required. Fancy doing one?

Another interesting project was the PalmerSport Jaguar XK-Rs, all converted to LPG only, no petrol system left at all. My job was to re-tune the engine management, which obviously involved a lot of thrashing the cars round the race track, it’s

25 thousand miles a year driven flat out, remarkable cars.

a hard life.

The next little project was a two pronged ebay ‘bargain’. I wanted to make a track day car for Di who loves E30 BMWs. I couldn’t find what I wanted so decided to make one using the tried and tested method of buying a car with the ideal shell but wrong engine plus a rot box with the desired engine. As luck would have it I found a mint 316 two door non-sunroof with MOT, plus a utterly rotten 325i with a really good engine and gearbox. Blending the two had a few problems but resulted in a track car at a fraction of

The scrapper 325i donated its engine and disc braked rear axle.

the cost of a mint 325. All the bits left over went back to ebay and paid for extras like the roll cage, which was nice.

A 316 transformed into a 325 for the track.


Another purchase with only a few weeks of MOT was a rather pleasant Range Rover classic. It was just a few hundred quid because it wouldn’t start, the owners ‘mechanic’ friend told him it needed a new fuel pump, ECU and some other expensive bits, but when I got it back to the workshop I found it was just a corroded wire on the ignition, a few

A broken wire had written off this RRC.

minuets and a new spade terminal and it fired up. I had only bought it for spares but with a few weeks ticket left it seemed rude not to drive it, surprisingly it drove very well, even Di who is a sports car fan liked driving it.

The Range Rover’s engine and auto gearbox was due to be fitted to a rather tidy two door Range Rover Classic belonging to the editor of PPC magazine, I also fitted the stainless exhaust that the donor car had plus the fuel injection. The resultant car was a rather pleasing blend of ’70s style and ’80s performance, it was also more economical.

I love the original 2 door Rangies

Sometimes I end up with a car that I have fixed for someone, such was the case with a Frontera that belonged to Di’s uncle. The car was at that age when one thing after another breaks, and after several trips to the workshop the owner got fed up and bought a Freelander instead, which needed less frequent mending. He offered the Frontera to me for a bargain price, I set about overhauling a few of the remaining items and sold it on, but not before driving it round for a few weeks and being surprised how much fun it was.

The Frontera; not as s##t as I thought.

Some of the project cars are more interesting than others, one of my favourites was the Escort which came in for a suspension conversion. The engine was a big turbo Saab unit capable of over 400bhp, to cope with this I fitted a narrowed Volvo 740 axle with a classic four link set up. The front received Group A rally suspension. This was a thing of beauty.

400 bhp MkII Escort, nuff said.

Occasionally I get called by magazines to help with their project cars, if you follow Practical Classic you might know of their very long term restoration of a MK2 Jaguar to which I fitted the wiring and a few other bits. A more curious call was from Evo magazine who were running a ‘Grand Challenge’ where they bought a shed of a car for under £1000 then raced them. One car, the BMW 325 cabriolet had virtually no brakes so it trundled into the workshop for a rebuild, I was not allowed to spend any money on it as this was against the ‘rules’ so I stripped and rebuilt them to stop the callipers sticking and resurfaced the discs and pads. This worked well, but when the young Evo staff member drove it back on a cold and frosty night he managed to loose it on a corner and crash it. Undaunted, for the next trial at Bedford Autodrome race track we recovered the ‘scrap’ from the insurance company compound, at the pits with the 325

Track day in the snow in a written off BMW, who hasn't done that...

firmly strapped down to the trailer and the trailer brakes applied I asked someone to stand on the brakes of the Range Rover tow car, meanwhile I attached a tow rope to the crumpled bodywork that was crushing the front left wheel and had smashed the front of the engine, the other end of the rope was attached to my trusty Discovery which I drove in the other direction with some enthusiasm, repeatedly wrenching the bodywork out until the wheel was free. I dropped in the radiator and intake from our E30 and fired it up. The only thing preventing the wreck from an outright win on the test track was the fact that it was snowing! Ever done a track day in the snow? You should!


My trusty Disco has a hard life and needed a major overhaul, so to keep myself mobile I put the word out on social media that I needed a short term banger. This Volvo 940 turbo was offered to me for £50, only snag was it had to be recovered from a secure compound on a military base! A few tweaks later it was roadworthy and its remaining month of MOT was well used as I travelled the country for various photo shoots, it even managed to survive driving round a quarry when I test drove a Bowler Nemesis for Evo. After a few weeks I had patched up my Disco again and the Volvo was surplus to requirements, now this left me with an expendable car with a turbo engine, you can guess what happened next, up went the boost in stages, testing the performance then upping the boost a bit more. Obviously eventually it went pop, but a lot of fun ad occurred.

The 635CSI, drive one, it's important.

A frequent visitor to my workshop was Di’s BMW 635CSi, one of my all time favourite drives but by crikey does it need a lot of maintenance, and the bits aren’t cheap either, a genuine set of spark plug leads is over 80 quid! The car arrived with the original metric wheels with odd sized and very old tyres that made the car lean to the left. I bought a set of BBS wheels with decent tyres and unsurprisingly the handling improved dramatically. These are lovely cars to drive, but if you get a cheap one be prepared for a lot of work.

Vrooom Pttttshhhhhh

The Saab 9000 was an accidental purchase, or possibly more accurately incidental. It had been converted for track day use and was offered to me with a view to me breaking it up. All I wanted was the seats! Anyway, it had the big turbo engine and a few tweaks, it went like stink and handled OK, after a short period playing with it I swapped the seats back to standard and put it on ebay, two young lads bought it. I explained that it was a bit swift and that they should take it easy but I never heard from them after they took it away, don’t know whether they got home….

Yes they are indestructable

As my workshop was on a farm I occasionally got called upon to fix farm vehicles, tractors, a combined harvester, Teleporters and even crop driers. They also had two very rusty Toyota Hi Lux pick ups, these were rarely used on road, they are registered ‘agricultural vehicle’ and don’t need an MOT. Which is just as well because this one would never pass one. Being caked in mud and farm waste permanently had rotted nearly everything, it was held together with wood and good will, it had structural bailer twine, it was a shed. On this particular day the brakes had failed and the car had been stopped by driving it into a steaming mound of farm waste and poultry entrails. The car arrived on the end of a fork lift truck and was dumped in my compound. Taking the wheels of resulted in a splash of what I at first thought was mud, but as soon as it started running off I realised was in fact cockroaches, woodlice and maggots. The brakes had failed because the pistons had fallen out of the callipers due to the discs having worn down to 0.9mm thick!


Another odd thing from the farm was the Kubota lawn tractor, which had a problem with the hydrostatic drive. The engine just drives a hydraulic pump and the wheels are driven by a hydraulic motor, in between are two swash plates so the gear ratio can be infinitely varied between two limits. You can drive along and steadily drop the engine revs whilst increasing the gearing to maintain a constant speed, if you wanted to.

With the arrival of our baby, our transport needs changed. Di heroically continued to use the 635 with a baby seat in the back but the contortion needed to get a baby into the seat eventually wore her resolve down, so she decided to get a Disco like mine, only cheaper.

V8 but no burble

It had a worn cam and a host of problems caused by years of neglect. I fixed most of them but when it became clear a new engine would be the best rout she decided to sell it, there comes a point when it is better to get rid and start again, the art is to recognise when this is and not get trapped into spending a fortune.


Another example of this was a Fiesta I bought with a view to doing up and selling on. It had been parked on grass, which is the worst thing you can ever do to a car other than burning it or rolling it! Grass creates a very humid atmosphere that eats very quickly into every nook and cranny of the bodywork, it eats the brakes, the fuel lines and every fixing that is in anyway exposed. Up top the car had been regularly washed and appeared to be looked after, but once back at the workshop and up in the air it became clear that every mechanical part under the car needed refurbishing or replacing. Both sills had rotted from the inside leaving a thin layer of paint to make the outside look ok! I decided to cut my losses, strip a few spares off for ebay and weigh the rest in for scrap.

This shot was for a CCW article on towing

A better choice was a lovely green XJ-S 3.6, bought with an engine fault that was reasonable easy to fix. These 6 cylinder Jags are lovely to drive, quite nippy yet very smooth and capable of returning over 30mpg on a run. Once it was all running well it was bought by a chap wanted it as a first car for his son, how fantastic is that!

I have also done a few experiments in the workshop when people have asked me to investigate theories or product claims. One of which was the idea that you can improve mpg by using hydrogen obtained form on-board

I test claims and say what I find.

electrolysis of water. I tried several variations and ran systems on my car for many months. Guess what, it doesn’t work!

Customer projects continued through the workshop including a rather cute MGB, it had a Lancia twin cam 2 litre engine and a Fiat five speed box. To get the power down I was asked to fit a modified Rover SD1 rear axle, parabolic leaf springs and convert it to use a Watts linkage. I was surprised how much difference it made, particularly entering fast corners where it settled in instantly rather than the traditional MGB rear end wobble. Must do an article on it one day.

Twin cam MGB in progress

To replace Di’s Disco she returned to her trusted BMW, this time with a 535, similar to the 635 but with 4 doors making fitting a baby much easier. These cars are often kept in very good condition but have amazingly low values, this one was under £300 and only needed tyres and front dampers for the MOT. Eventually she sold it to a collector in Dubi!

At this time I started doing higher mileages as my technical consultancy work really took off, I needed something a bit more economical so I bought a Rover 420 diesel. Fantastic car and cheaper than the smaller 220 for some reason. In a year of motoring it only

Top Gear test track in a banger

needed routine servicing and one new wheel bearing. I absolutely thrashed it, including a few laps on race tracks and running down the beach at Pendine. Only down side was I found the seat very uncomfortable.

I got a call one day from a bloke who wanted me to get his MGB working, this sounded ok until I saw it parked in a hedge, one side rotten the other side missing! I declined to fix it but did use some of its parts on his other MGB. Amazingly this chap bought two identical


new MGBs back in 1980, he used one (the one in the hedge) but kept the other one under wraps in a dry garage. It had last ran 20 years ago and had a few thousand miles n the clock, even the running in instruction sticker was still on the windscreen. I changed the expired fluids, cleaned the plugs, stripped and rebuilt the carbs to free them up, fitted a new battery and threw some fresh petrol in. Amazingly it fired up first time! I freed off the brakes and took it for a drive round the farm access road (private land), it was an utter time warp car and an amazing experience.

Stunning originality

As time passed Di’s BMW started to show its age, and in the winter snow it was a bit to lively so she decided to try a Disco again, this time a ‘spares or repair’ Discovery 2 V8 with a faulty LPG system. The car was basically sound but had suffered from a lack of maintainance and a botched LPG conversion that had damaged the engine electrical system. It was a mash up of random LPG parts that would never work together but the tanks were ok, so I first reworked the wiring to get it back to standard and running

where angels fear to tread..

properly on petrol, then fitted new brakes and gave it a full service, it passed the MOT with ease. I then bought a second hand LPG front end kit to get it all running properly.

If you follow Twitter you may know @onecarefullowner, he has a dream of fitting a Rover L series Diesel engine into one of his beloved Allegros. I like this idea, double the power and also double the economy, double win. The target for his Frankenstein concept was a slightly battered white estate which in tru tradition ‘looks worse than it is’. The engine donor is a Rover 220d, it is always best to have a complete car to take the engine from so that you


get all the ancillary bits needed for the conversion. One small problem is that the L series doesn’t fit in an Allegro engine bay, you have to cut off the chassis rails! The solution would be to weld in a space frame front end, but this was beyond the scope of the original project and Richard took the difficult decision to quite before we ran out of time.

Richard and the donor

Other vehicles that have gone through the shop include a variety of bangers, the Audi 80, Pug 206, Freelander and my Rover 75 plus @petrolthreads E30 race car and a few prototype cars for OEMs, but that’s another story.

With my time totally consumed with consultancy work and writing I closed the workshop for the last time in October, it is sadly missed.

The GT Double 6, Triumph GT6 meets Jag 6litre V12
My long suffering Disco, still working hard
E30 'testing'

First casualty of adversity

There is a saying in the army; something like the first casualty of any war is the plan. This reflects the fact that in adversity normal rules fail, but it is not restricted to war zones, there is a battle raging on all around us and on our streets right now.

If you starve a colony of rats they will eventually start killing each other, so I’m reliably told, to reduce the burden on the available food supply. They start by turning on the weak and old, then turn on the outsiders and any member of the community who is unusual in any way. We do the same, in fact most creatures do this to survive.

The instinct to turn on some members of the community when times get hard can be seen in the ridiculous way that some drivers demonise drivers of other types of vehicle. We all feel the pinch from fuel prices and many of us feel guilt at CO2 output, and whilst this drives some of us to find better ways to get about and to develop better cars, it also drives some people to blame minorities for their own perceived plight. One example that effects me is the way 4x4s are attacked. We have two Land Rovers, and they are used for heavy jobs but not for long journeys so their annual CO2 footprint is quite small, but that doesn’t stop 4×4 haters putting anonymous hate mail under the wipers and campaigning to ban them. The fact that a 20k mile a year Micra chucks out twice as much nasty each year seems to escape them.

Right tool for the right job, different cars have different uses but room for everyone.


This is just one example where society fragments and one section turns on another. Unfortunately all this does is consume energy and resources for no useful result, surely their cause would be better served if our energy is whole heatedly put into solving the problems of CO2 rather than banning this or that sub set of the community. In the UK 4×4 all terrain vehicles count for a very small percentage of the cars on the road, and their lower average mileage means that even with a slight increase in fuel consumption they contribute a minority of the road vehicle CO2, so banning them is not going to help anyway, and crucially all the media attention takes attention away from the truly important debate on how we stop CO2 emissions completely. (And before you go off on one; yes this does assume the CO2 issue is real, I am not going to get involved in that debate as I don’t have enough detailed knowledge to make a positive contribution, but in the context of this article it serves to illustrate how society fragments and how this is counter productive. So please don’t have a go at me about CO2)

Manufacturers are chucking huge quantities of money and resources into solving these big problems, but making plans for future eco products is hampered by the car buying populous constantly bickering amongst themselves about what sort of car is best, for example Ford has repeatedly tried to sell electric city cars such as the Think which was available a decade ago, but no one bought them. We have the hybrid fanciers and the hybrid haters, each throwing salvoes of misinterpreted data at each other to prove their own point of view. We have the big car lobby and the small car evangelists undermining each others right to exist on the road. Performance car enthusiasts are put against green car preachers, each striving to point out the pointlessness of the other’s point of view. The fact is we all have the same right to be here, we are all part of the problem and simply fragmenting will not solve anything.

Rolls Royce have gone to great lengths to demonstarte their EV technology really works.


Imagine if instead of finger pointing we actually joined forces, with car sharing on each part of the street so that one families diesel estate got used by many families for their annual holiday, or the neighbours 4×4 was available to anyone in the community to borrow for really big jobs and getting provisions in the snow. There is no technical obstacle to this, but there is a massive attitude problem which kills the idea dead. In any scheme like this someone always get disproportionately more benefit than someone else, but so what? As long as everyone in that group gets enough benefit what does it matter if someone else gets even more? But most humans rarely think like that.

Of course it is not just the car world that has this problem, recently we saw public sector strikes that seemed to resolve everybody’s opinions either for or against, most opinions seemed to be formed with the minimum of data and the maximum of social prejudice. For my part I voiced the opinion that I found it difficult to agree with the strike when we were all suffering from financial hardships, notice I did not say I disagreed with it, just that I found it difficult. In this example there are genuine grievances, if I signed up for a job on the promise of a good pension and several years of hard work later it suddenly gets taken away then I too would be bloody fuming. Clearly this aspect is a very bad thing to do. But when we look at the other side we find that there simply is not enough money to pay for this as well as everything else, this is a very big problem that has been brewing for many years and is suffered by most western countries. In this case both sides are right, the solution is to generate more wealth to pay for the promises whilst adjusting the terms of employment for new recruits, or something along those lines possibly. But rather than have a national debate about how to fix this and coming up with ideas, we are instead once again fragmenting into ‘sides’ and just having a slanging match.

My V12 Jag racer would use 50 litres of fuel per race, but this was only 8 times a year. Some want to ban racing but commuting uses far more fuel! We need a solution to all problems, not a ban on minorities.


Then there is the current hatred for rich people, it seems that anyone who has managed to amass a decent wedge must be vilified for the obviously evil methods they used to steal the cash of the hard working whatever. Again this is pointless, there are freeloading useless people in every sector of society, no one has a monopoly on bastards. But instead of discussing how we can all get a bit better off the argument descends into taking money off rich people to give to poor people, and in doing so fragments society into those who have money and those who don’t, rather than joining forces and generating new businesses that add value and generate wealth.

My message is a simple one; stop attacking and start building. Time is running short, and there’s a storm coming.

Running cars on water

Can you run your car on water?

There have been many stories of genius inventors making a car that runs on water, only to be silenced by the evil oil companies, never to be seen again.

Can you run your car on water? Well, not like this, obviousely.

I was intrigued by the sheer volume of technical claims, despite decades working at the cutting edge of automotive technology and being immersed in scientific theory I am acutely aware there is always room for doubt, and for new ideas to surprise and change the way we think. Ideas like these are rare but happen often enough to make keeping an open mind and essential part of the make up of the modern engineer.

The traditional view is that water is basically hydrogen that has already been burnt, so it has no usable energy content left. Because of this fact there is a tendency to think that all these people who believe in water power are all nutters who probably have been abducted by aliens and experimented on for a laugh and are a tiny minority. But nothing prepared me for the depth and complexity of the technical explanations and the shear volume of conspiracy theory’s involving governments, car makers and oil companies all in cahoots to keep us buying expensive oil.

Well, let me assure you that car makers would quite happily stab the oil companies in the back if they could sell a few more cars, and one that ran on water would sell rather well, don’t you think?

So, how do you run your car on water?

Well, you will need a big plastic jar (screw top with a good seal), a small plastic jar, some tubing, a few strips of metal, some small bolts, a fuse and some wire.

But before I go into details, I want to talk about electrolysis. I found a number of amusing web sites that propose the use of hydrogen made from passing current through water. So far that’s not a bad idea, many car companies are investing quite a lot in converting petrol engines to run on hydrogen.

Where these sites go off the rails is when they generate the gas on board the car, using electricity from the alternator, which is of course powered by the engine.

Here are some basic figures for you, a good car engine will convert 33% of the energy released from the fuel into usable power at full throttle, it goes down to about 10% at light loads. An old carb engine might be as poor as 20% at full tilt. Oddly enough big engines can be more thermally efficient than small ones, its all to do with heat loss and the ratio of volume vs surface area, the most efficient piston engines in the world are the cathedral engines in super tankers, such as the 25 thousand litre Wartsila-Sulzer RTA96-C turbocharged two-stroke 14 cylinder, which gets up to 50% efficiency. You may recal I did a blog post about it last month, its very impressive but at 2300 tons you would struggle to get it in a car.

So, going back to our in-car hydrogen plant, with the precious little power left at the crank we drive the alternator, which usually has quite a good efficiency, converting about 90% of the power fed into it into electrical energy.

Then there is electrolysis, at the molecular level, the energy you put in to separating water into hydrogen and oxygen is the same energy you get back when you set fire to it. Interestingly, some of that energy can come from heat from the environment, ie the heat from the engine.

So, when you add up all those efficiencies up, to produce 1bhp worth of hydrogen, the engine has to burn nearly 4bhp worth to make the process work.

Guess why it doesn’t work!

Mind you, if you generate the electricity away from the car, say from a wind turbine in your back garden, store the gas in huge explosive bags attached to the roof of your car then you are on to a winner. Until it imitates the Hindenburg.

So once again I have shown that you can’t run your car on water. So now I will finally get round to showing you how to do it.

One of the reasons that the efficiency of car engines is so low is that not all the petrol gets burnt, and some gets partially burnt. The actual combustion process is very complicated, with molecules decomposing into sub species before reforming into exhaust gasses. The flame front travel across the cylinder is also semi-chaotic and some molecules get passed by entirely. Some start burning then hit the cold cylinder walls and stop burning, some start burning at the end of the process when the piston is to far down to convert it into usable energy. Petrol mixtures burn at a rate of about 40 to 50 centimeters per second depending on loads of factors like pressure, turbulence and temperature. That’s one of the reasons that big engines run slower as it takes longer for the flame to travel across the bigger combustion chamber, for instance that super tanker engine I mentioned produces 5 million ftlb of torque at just over 100 rpm.

If we could speed up the burning process then more of the petrol’s energy can be converted into useful work on the piston. Also, if we could put in something that would mix more readily with the air and bridge the gaps in the fuel mixture we could avoid those dead spots.

Ooh, hydrogen does that, it mixes very readily and burns faster. So all we need is a very small amount of hydrogen and we can improve the efficiency of the petrol.

The difference in power at part load by introducing a sniff of Hydrogen.

Well, if its so good why hasn’t it been done before? Well, it turns out that this method has been used for many years and some reasonable research has gone into it, have a trawl through the SAE web site and you will see that many respected institutions and big companies have published papers on the subject. Some use methane which is broken into hydrogen and carbon dioxide by the use of rather hot steam. Of course you then have a hydrogen car that produces co2 which is sort of bad really.

So here is the theory; you get a bucket of water strapped to the car, stick two bits of metal in it (electrodes) connected to the battery (via a switch and fuse). The lid on the bucket has a hose to transport the explosive hydrogen and oxygen gas to another bottle where any water is removed (don’t want to hydraulic the engine). Finally the hose is stuffed somewhere in the intake to allow the gas in.

Great, but how much gas do we need? Well, to make 1g of hydrogen you need to apply 285Kj of energy to the water, luckily the water tends to use energy from the environment during the process, so potentially about 48 Kj of heat will come from the engine bay, leaving our electrics to provide about 237Kj per gram.

Now, power in Watts is Joules per second. So 1.4Kw (1 HP) is 1.4Kj per second. Which works out equivalent to burning about 0.006 grams of hydrogen per second, or in volume terms that’s about 0.066 litres per second, a steady stream of small bubbles.

So for a cars electric system to put in 14Kw of power at 14v the current will be 100 amps, which is a lot.

But remember we are not talking about using the hydrogen to power the engine, but to help get more useful energy from burning the petrol. So the big question is how much do we actually need? The web sites suggest one litre of water will last up to 900 miles. That works out at about 1.1g per mile, and of that 1.1g of water there is only 0.12g of hydrogen per mile. At average speeds this works out at about 0.0013g/s, about one fifth of a bhp, less than 1% of the overall fuelling and will draw about 10 amps in the electrolysis bucket.

To get a sensible answer to all this, I nailed some scrap metal into an old washing powder tub and tried out some combinations.

First attempt, stainless steel wire in plastic formers.

The first version was one recommended on an American web site, claiming up to 40% gains in efficiency. It consists of a one litre plastic container with two bolts in as electrodes. But even with a little salt added to my copy it only managed to draw 0.1 amps and no detectable gas flowed out of the outlet hose. In short, it was useless and had no effect on the engine.

Clearly we need more power, one of my favourite sayings. So next we have a system with drastically increased conductor length by using wire, wound round a cross shaped former, still in the one litre pot. This has the effect of drawing 10 amps, about where most of the internet products are, and a steady stream of bubbles.

Second attempt after a few thousand miles. Third version ran cleaner.

This very small amount of gas will have the most dramatic effect on the engine at lower loads and idle because that is where it will be the biggest proportion of the total mixture, so I fitted the system to the intake and watched the injector pulse widths and lambda compensations so see what effect it had. Well, the web sites suggest a 30% fuel saving overall, so at idle it must be huge, but no, there was absolutely no difference on average.

I even drove it round for a few weeks, and at first I though I could just detect an improvement in power and the fuel bill seemed to be dropping. But then it went up again; it turned out that it was just me driving more carefully as I paid more attention to what I was doing after fitting the kit. This is a very common phenomenon.

First instalation, about to test current and voltage on my long suffering Land Rover, subject of a great many experiments...

So how much gas do I need then? Well, some very useful research has been done by NASA and various universities. Basically to get a 30% increase in efficiency (power out vs fuel in) we need to run 90% hydrogen/10% petrol!

At 50 % hydrogen the efficiency improvement is only 15%, but what does that mean in a normal car? Well, if you are cruising down the motorway you might be using about 20kw of engine power, if you only run 50% HHO then that’s 10kw of electricity running through your jam jar, at 14v that’s over 710 amps out of your alternator! But then that power comes from the engine so it would now have to produce over 30kw, which would mean a 30% increase in petrol use in order to gain a 15% efficiency saving….. Hmmmmm..

Now, bear in mind that the average driver can improve their fuel economy by up to 30% just by learning better driving techniques, and that on an average commute fuel economy can vary by 20% easily depending on what mood the driver is in. So subjective assessment of 10% economy gain is meaningless, it has to be checked on a proper test facility.

There are of course other ways of generating hydrogen on board a car, using chemical reactions, and this would take the alternator problem out of the loop, but generally the chemicals are rather nasty/expensive and leave a chemical waste problem.

One of the favourites being explored by the car industry is called ‘reformate’ where the petrol is partly separated into CO2 and Hydrogen using a catalysts and exhaust heat. At the moment the fuel savings don’t justify the expense of the extra equipment, but I am sure that will change in time.

Water has a number of other benefits in a traditional engine, I am sure you know about water injection which turns a bit more of the heat energy from combustion into pressure energy. It also reduces cylinder temperatures and so reduces knock, allowing a bit more advance. But also a small amount of water, up to 5%, if well mixed in the fuel before its injected can increase power by up to 7%. Unfortunately you cannot just chuck a cup of water in the fuel tank, because it wont mix, you need some reasonably clever and accurate mixing machinery.

In short, there is a lot you can do with water. However, if you google ‘water car’ then the myriad of websites that appear generally talk complete twaddle and make excessive claims for there own brand of hocus. Whilst I am talking about the web sites, there were a few claims that I feel are potentially harmful.

First is the matter of your cars warrantee, unlikely anyone thinking of doing this will have any, but the point is that despite the various web site claims, fitting absolutely anything to your engine will invalidate the warrantee. In the car industry we spend a huge amount of time and effort checking the car works under all sorts of conditions, it takes years for each model to complete all the tests before being ready for production. Modern engines are so finely tuned that any disturbance will cock things up, and that includes those plug in chip tunes by the way. So plumbing in a bottle of water to your intake will definitely lose any warrantee.

Next, some sites sell you electronic devices to bias engine sensors to make it run lean, best fuel economy generally happens when you run 10% lean of stoich, which is fine at part load on a non cat car, but obviously not at full load because things overheat and fail, and if you have a cat it will stop working eventually. And as these are sold without checking the engine on a dyno the potential for detonation or catalyst damage is rather significant.

Then there is the matter of additives in the water, remember it all goes somewhere and some chemicals will put quite nasty things into the atmosphere. Some sites advocate volatile fuel additives too, again the reason the car industry doesn’t do this is that it poisons the catalyst and puts very nasty stuff into the air. Fuels with super chemicals that don’t pollute as much are readily available, such as Shell Optimax or BP Ultimate which have over 200 chemicals in to get the best performance.

Safety seems to get a fairly low priority too. Remember that as we separate the water we get a perfectly explosive mix of hydrogen and oxygen, albeit in very small amounts. If the pot you generate the gas in is not ventilated then any slight spark could leave you pot-less and potentially destroy things under the bonnet. Luckily most of these systems produce so little gas that it is unlikely to be a problem!

So in summary, yes you can run your car on water, but not using a jam jar and some wire.


Don’t just take my word for it; here are some of the research papers I used in my research:

SAE 841399 1984

Water/fuel mixtures

SAE 740187 1974

Lean burn with Hydrogen supplementation

General Motors Corp.

SAE 810921 1981

Lean burn with Hydrogen supplementation

University of Michigan

SAE 2004-01-1270

Hydrogen reformate (H + CO2)

Robert Bosch GmbH

SAE 760469 1976

Hydrogen reformate in aircraft engines

Jet Propulsion lab

What are the losses?

The heat released from fuel is mostly wasted, about a third goes down the exhaust pipe (turbos can recoup a small fraction of this) and another third goes into the oil and coolant. A smaller amount is wasted as noise and vibration.

At part load the throttle causes an obstruction that wastes power too. A better solution at part load is to replace the unwanted air with an inert gas, this allows the throttle to open up and reduce losses. That is why Exhaust Gas Recirculation (EGR) can improve economy by 5%.

What is reformate?

This is where the petrol is broken down into hydrogen and carbon dioxide. The CO2 is inert and at part loads is used as ‘padding’ allowing higher throttle openings, this reduces the throttle losses and also improves efficiency. This double benefit is why the car industry is concentrating on this way of making Hydrogen. But with the petrol engine’s days numbered, the technology may never mature.

What is HHO, Oxy-hydrogen or ‘Browns Gas’?

This is what you get from electrolysing water, it is simply oxygen and hydrogen in a gas. There is a lot of myth about it, but here are the facts: It burns at about 2800 C, compared to about 2000 C for petrol in air, or about 3000 C for oxyacetylene welding kit. In fact it was one of the first gasses for welding, but in slightly richer proportions. When HHO is burnt in air, as in our engine example, the flame temperature drops to similar values to petrol.

When it burns it expands, and so can be used to power piston engines, then it forms water vapour and starts to condense, rapidly contracting into just water.

The gas has been the subject of many hoaxes, frauds and misguided optimistic claims.

It’s not magic, just nature. Although personally I thing nature is pretty magic.

The genesis of the Jaguar V8

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

Potent as the V12 was, it weighs about 350kg on its own! As I found out when I built this XJ-S...

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.

The Jaguar V8 would also make a damn fine race engine...


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.

The new XK was launched with the revised 4.2 V8, a swansong for the first generation V8.


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.

Land Rover with Jaguar V8 power, a rather good combination in my opinion.


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.

From E Type to XJ supercharged 5.0 V8, innovation lives on.


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.

An experimental race vehicle recieves the new 5.0, light and strong with a tuning potential well above 600bhp.


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.