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I was testing a compact SUV the other day, it’s spec sheet fits in nicely with the current competition; about 240bhp in a 1400kg car, 4WD and 0-60 in the region of 7.9s. Although this may not be earth shattering performance by modern standards it set me thinking, about two decades ago I was working on a car that some of you may of heard of; the Escort Cosworth.

Now the Cossy set the world alight with its ‘blistering performance’, even that bloke Clarkson had one of his own and spent far too long telling everyone. Part of the Cossy legend comes fro the fact that in full rally cross tune it could hit the dark side of 600bhp, but even the standard version was in reality rather quick.

But now the Focus five pot has more than 300bhp and luxury saloons must have 500bhp to be a serious contender. Things have clearly moved on, but surely an old quick car is still a quick car? If I hopped into a Cossy today would I be bored rigid with it’s hum drum performance?

So I did a highly un-scientific poll on Twitter, asking people what felt quick to them, and the results were remarkably consistent, although that might just be an indication of the type of people who follow me!

Allegro fan extraordinare @OneCarefulOwner commented “the goalposts have moved in a major way; my Maxi 1750HL had a blistering 96bhp, nowadays small diesels have more grunt.”

@racing_waiting pointed out that defining quick was a well trodden path “tricky question, drivers republic struggled, imotor struggled, road my previous mag stuggled.”

On the subject of the old XR3i @HairyCalahan observed “times have changed. expectations too. xr3i fine for it’s day”

But getting down to numbers @vHenryk considdered that “pretty much. A ‘sports car’ doesn’t have to be a ridiculously expensive 0-60 in less than 5 secs thing to deserve the name.”. Whilst @torquespeak said “Puma convinces me anything above 120 has a decent shot. 8 secs to 60 not first degree rapid but a hoot on the twisty bits!”

Of course power and weight are only part of the storey as student and car nut @MrPA sugests “On a decent road anything can be fun. I have a few corner-filled favourites which are brilliant in my mum’s 1.2 Clio (75bhp!).” a fair point and one echoed by @cotswoldracer “Indeed , my old AX GT 700Kg & 85bhp , and going by memory about the same as my 145 in terms of acceleration (8ish secs to 60), my Alfa 145/950kg/150bhp quick-ish , another 35 bhp would make it even more fun :)”

@carpunk observes the importance of weight in its own right “Guess 100hp in a 1000kg car will always feel much quicker than 250hp in car 2x the weight because of inertia, braking mass etc “ and @jonbradbury agrees “I think modern expectations have increased, & so has most weights. Though 160hp in 1T 944 shifted lot better 115hp Gti & the 115hp GTi shifted better than the 115hp XR3i.”

The consensus seemed to be that a ‘sports car’ of between 1 and 1.5 tons should have between 180 and 250bhp.

Which brings up some interesting points, firstly that a lot of ordinary family cars are actually high performance sports cars, and it may well be that the only reason that they are not regularly parked in hedges and Armco is the astonishing amount of technology dedicated to combating incompetence behind the wheel.

But going back the that point about the way cars feel, this fantastic driver assistance seems to have come hand in hand with a duller edge to the driving experience. Back in the day a sports car would engage and entertain the driver, not only with its performance but also with its ability to snap back and slap the unwary in the startled face. Putting your foot down in a high powered car not only thrilled but also surprised many a driver when glancing at the speedo to see the needle significantly further round than expected. Over enthusiastic cornering could result in the car suddenly swapping ends or having less wheels on the ground than is healthy. Motoring enthusiasts call this sort of thing ‘fun’, but unfortunately normal people call it dangerous, and so because there are more of ‘them’ buying cars than there are ‘us’ cars have become less dangerous, and sometimes less fun.

But from an engineering point of view fun and safe can co-exist. Some manufacturers have cottoned on to the fact that whilst safe and dull is best for the mass market there is still a significant market for thrilling cars, and having driver aids set to only come in when disaster is otherwise inevitable yet allowing a reasonable degree of sideways progress makes good sense.

For instance if you turn off the traction control on a Jaguar XKR you can light up the tyres and do doughnuts, but you will still struggle to accidentally oversteer backwards into the vicars rose garden because the system is still active and helping the driver achieve their intended trajectory. I have driven one with the traction control completely removed, and to say one needs ones wits honed and ready for extreme service is an understatement, it’s not fun on a wet B road – it’s simply scary.

Maybe 500bhp is fine when controlled by modern electro-wizardry, but has the same thrill factor as a raw 200bhp in a car with no aids at all. So how much power does a sports car need? Well it would seem the definitive answer is ‘it depends’.

Brakes are all about heat, and ditching as much of it as quickly as possible, they work by converting the cars speed energy into heat energy which is then taken swiftly away in the air streaming through them, in theory. But a big car at high speed has an awful lot of energy; for instance getting a big car to do an emergency stop from high speed might put the equivalent of a thousand bhp through the brakes make the discs glow red.

There are two basic types of brake, drum brakes get their name from the drum of steel with curved shoes inside that are pushed outwards against the inside of the drum when the brake pedal is pushed. These can be found on the back axles of cheaper cars and are quite frankly a bit pants; the braking force is limited by the drum wanting to explode, plus the pistons are small and the pressure pushing the shoes out into the drum is similarly small.

By comparison disc brakes can exert a much higher force onto the disc without risk of it failing.

It uses a disc with a set of pads held in a calliper that are forced against both sides of the disc when the pedal is pressed, generating much more force.

In both cases the disc or drum part is attached to the wheel hub so it rotates with the wheel and the pads or shoes are held stationary on the axle, or strut, or what ever dangly bits are attached to the suspension.
All brakes work by friction, pressing a pretty darn tough pad of friction material against the spinning metal, the harder the friction material is pressed against the metal the more friction is produced and the greater the braking force.
Brake systems use a special type of high temperature hydraulic oil to drive the pistons which push the friction material into the disc or drum. At the pedal end there is another piston in the master cylinder which is connected by hydraulic brake pipe to the slave cylinders at each wheel. In some cars the brake force is artificially increased by a servo directly connected between the brake pedal and the master cylinder, this uses vacuum from the intake manifold to move a large diaphragm when the brake pedal was pressed, as the pedal moved down small holes in the servo control section are progressively uncovered which applies more vacuum to the diaphragm which in turn applies a greater force to the master piston of up to four times the force at the pedal.

Some cars with Anti-lock Brake Systems (ABS) use a powerful electric pump to do this instead. The ABS system measures wheel speeds and if it detects that a wheel is slowing down faster than a safe limit then it knows that that wheel is about to start locking up, so it lets the brake pressure off the individual wheel by opening a solenoid valve in the ABS valve block, just for a tiny fraction of a second until the wheel frees up just enough to know it wont lock. You can feel this when it happens as a sort of buzzing or vibration under the brake pedal. ABS allows maximum braking force without the risk of skidding. But if you are going to fast then you are still going to crash no matter what the brakes do.
The fierce heat generated from heavy braking has to be dissipated into the air which is why race cars have ducts taking fresh air from the front of the car to the disc centre, the hot air then has to go somewhere and the design of the wheel should allow it to escape readily. To get more heat into the air some discs are vented with radial channels cast into the disc to draw air from the centre outwards, some discs also have small holes drilled through for even more ventilation but these can lead to cracks starting unless they are made very well. Groves on performance discs can help remove the tiny gas layer that build up between the pad and disc sometimes and increase pad bite, the down side is that they can increase pad wear when used aggressively.
The brake size needed on a car depends on its weight and how fast it is likely to go, more powerful cars can more readily get up to higher speeds they need bigger brakes. Bigger pistons and a larger diameter disc make better brakes. Also if the brakes are going to be used for long durations, such as when racing, there is less time between brake applications for them to cool down adequately, this is where vented disks can be a real benefit.
All that heat soaks through the system into the brake fluid and although it is engineered to work at these very high temperatures in extreme cases the temperature can get high enough for the oil to boil, this generates gasses which compress easily and make the brake pedal feel very soft. This is brake fade and in really bad cases the brake pedal can sink to the floor with very little braking force generated, pumping the pedal up and down a few times can sometimes help but basically if the brakes fade on a race track then the standard procedure is to crash. That is why on roads with long descents the car’s speed should be controlled by using a low gear and engine braking rather than holding the brakes on for extended periods.

Most brake fluid absorbs water which boils and fades much more easily which is why it must be changed every few years to stay safe. Silicon based fluid is different and doesn’t absorb water but moisture still pools inside the system and needs flushing through every few years, it’s also a bit more squashy than mineral fluid making it unsuitable for fast acting ABS.

Brakes are often overlooked and any wear only becomes apparent at the mot or in an emergency stop. The trouble is that they have a hard life and can disintegrate with the friction material splitting off the steel backing or wearing down to nothing unnoticed, and they usually seem to work fine right up to the point were they don’t work at all and you crash. Maintenance and regular inspection is vital.

Larger brakes with a greater surface area to dissipate the heat into the air can cope with harder use but very large brakes need large wheels in order to fit. But all the force generated by the brakes has to be transmitted into the road by the tyres, so if the brakes are already capable of braking traction then there is little point upgrading them before upgrading the tyres. As ever the best solution depends on how the car is to be used.

Technology is fundamentally changing journalism and will ‘kill off’ the traditional idea of a journalist, or so I’m told.

If you think about it the traditional model of journalism has a very few journalists talking to the many readers much like the Queen addressing the nation, but with more queens. This may be because the traditional methods of mass communication, papers and books, was very expensive, time consuming and required specialist skills. But also because a small elite had vested interests in controlling information to a greater or lesser extent.
However now anyone can communicate to potentially the whole world, more or less for free. Everyone is a journalist, albeit not necessarily a very good one.
First the internet democratised information flow, but now mobile phones are the main information sharing method for the new generation. The devices are small, portable and cheap, you can view content in private or share with friends very easily. Content can be shared via the phone network, the internet or directly via Bluetooth, so people can share localised information within their own clique, forming their own virtual information hub. I noticed this particularly when I was teaching engineering to 16-19 year olds, they shared videos, music and information on phones leaving the internet as a secondary source, TV and magazines hardly got a look in.
Images are often a large part of content, and newer innovations such as iPad and smart paper will be welcomed, but the handy small screen phone device still has the winning formula for most.

So thinking that in some way controlling the internet will control information flow is wrong.

I became a full time journalist only a few years ago, but I am very aware that the life of that role is limited, and maybe in less than ten years it may have completely eroded.

But even with the need for a ‘speaker’ removed, I think there is a natural human tendency to elect locally respected sources of knowledge. Every web forum has one member that everyone turns to for advice.

So in the future there may still be a role for a well informed and competent communicator, the trouble is from an practical point of view that there is no intrinsic method of financially rewarding this role; information is fairly free now and hopefully there is no going back. We are all less inclined to pay for magazine articles when we can read it for free on the web, and despite the huge amount of dross and misinformation that’s about there are still plenty of well informed bloggers who report events very well, some post excellent photos and videos too.

Currently there is still a place for magazines and tv stations, because of the uncertain and variable quality of free media we need somewhere apparently reliable to turn to. But as social networks establish, an reliable free sources are clearly identified, this need will transfer from the paid for media to the free.
We live in a time of great change, traditional roles and social models are being erased from the ground up, content providers such as magazines and tv companies must work with this to make new opportunities, to resist change is to invite disaster.
Me, I’m just trying to pay my bills, and if I want people to carry on paying for my words then I suppose I will have to find something more valuable to say.

Ralph Hosier 1-November-2010