Safe Speed Forums

Aye, it's a little unfair - but there are still plenty of ways one can cock-up the front/rear brake force distribution or some other feature of the braking system on a production car.

Suppose (and I'm not at all familiar with the Nova's braking system!) that one finds some bigger front brake callipers off the go-faster model but you don't change the rear brakes to match the fronts. That could alter the brake force distribution. Suppose also, that the master cylinder was different on the go-faster version because it didn't quite have enough travel for the additional volume of the bigger pistons under panic braking conditions... Or suppose the "G-valve settings and / or pad materials /pressure limiting valves were different...

Also, there's the situation where the rolling diamter of the wheel might change (as a result of the 18" touring car alloys that have been fitted!) and this will obviously change the braking torque needed to lock the wheel. Swapping the entire braking system for the next one up probably is going to be OK but it's realy hard to know without access to the manufacturer's data.

As for the mods being gradual, yes, that's true and it does seem a bit cruel to ask for an SVA test each time. I can't think of a better way though. Maybe a partial SVA test could be the answer? It would be an administrative nightmare though!

We probably all need to agree on a definition of "good" brakes here. Most people who get into my car moans about the brakes being lousy. They're not lousy, they're just not as ridiculously over-servoed as most modern cars! My wife's Alfa 156 is a pefect example of this. It's the "poverty-spec" 1.8 model so it has solid front discs (yes, 140BHP, supposedly sold as a "sporting" saloon and in this day & age it doesn't have vented front discs)!!! When you get into it at carpark speeds, it is almost impossible to brake gently enough. You've only to fart near the brake pedal and you're through the windscreen. Everyone says what fantastic brakes it has but they're crap in reality. There are a couple of hills near here where I can pretty easily start them fading - and that's just with me in the car! On my car, you need to give the brakes a heft shove but you can't (in road use anyway) get them to fade under the same circumstances - they just keep stopping the car.

I'm therfore not sure the level of pedal effort at which lock-up occurs is any useful measure of braking performance. After all, if you jus thad a pin that went through the disc and locked the wheels solid, the car would take longer to stop.

As we keep getting told, the function of the brakes is to turn the car's kinetic energy into heat AND then get rid of it as quickly as possible. To my mind, a good set of brakes will reach operating temperature very quickly but then take a long time to exceed it. This really means being able to use as much of the tyre's grip all the time as possible. With my wife's car's brakes, they tend to use all the tyre's grip initially and then fail to make the most of it when the going gets tough.

On the other hand, on modern cars, I suppose there is the argument that it is better to just make the brakes as light as possible and leave the ABS to sort out any excess pedal effort when panic braking!

The whole argument about charging for better training, or better testing involves costs which are tiny compared to the costs of insuring many of our younger drivers!
Mike in Northern Ireland paid £2,600 to insure a Ka!! Jamie Duff quoted somebody paying £2,800. £200 to check your mods are not going to kill you (without help) is small change compared to the insurance. Maybe Insurance companies should consider the benefits to THEM of improved training, and testing, and offer more incentive to drivers than they do at present.

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

I wonder whether the additional cost would have the effect of making them think twice before modding, then save up and do a lot of mods at once or whether it would just encourage them to rack up bigger debts. I suppose a side-effect would be that the companies purveying the go-faster bits might actually stump up some money for some proper testing so that they could sell the various goodies in complete packages advertised as being "complaint" with whatever bit of legislation was appliccable.

The extreme opposite end of the scale is what (I'm told) happens in Germany where you can't so much as fit an air freshener or set of furry dice without them being "TUV" approved! Apparently the registration document contains a comprehensive list of modifications that have been made to the vehicle but I don't know how that can be true because I thought the whole of Europe was on the new "harmonised" registration document like we currently have?

Knowing "ripoff britain" the manufactures would soon jump in and get the law changed so that they were the only ones to approve the mods possibly only factory trained techs could do them. (A la servicing under warranty that they fought tooth and nail to hang on to )
Of course with this would come a "certificate of conformoty", and a £1 bolt and nut would rocket to a lot more (as witnessed in a lot of industries where certificates of conformity are the norm)