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Cut the guy some slack! His car is on fire here!

I have a problem with their answer about the brakes. I have seen many photos of racing cars with the disks glowing cherry red in long races, say LeMans (24 hours) with no fire, no warping of rotors or claipers. It sounds like a major design problem with the car in the discussion.

You don’t suppose they might be using specialty brake materials in a race car designed to brake constantly from high speeds do you?

Apples->oranges comparing race car components to cars produced for the unwashed masses…

Maybe a slight re-hash of the question and answer would help for those of us that have conflicts during the show airing.

I don’t think it is a design problem wih the car. That seems unlikely. I think there’s either something wrong with that particular car’s brakes – like a caliper is sticking, a hose has collapsed – or something has been installed – pads, brake grease – that isn’t up to the manufacturer’s OEM specs.

I, too, had a problem with Click and Clack’s response. They used the term “grease” - and while there may be grease in the system, there is also some anti-rattle compound that is commonly put on that shouldn’t be called “grease”.

Is it possible that real low temperature grease was used in this area - and that was what was buring?

I note that the fire didn’t last too long, so whatever it was, either completely bured off or would only burn above a certain temperature.

You too can have carbon-carbon brake disks like the racecars…for about $2000 per corner.

As others have said, nothing in a racecar resmbles the parts in a production vehicle. These brakes are designed to withstand temperatures far in excess of production vehicles. And the racing brakes have to be heated up to work well.

Exactly. That race car costs a million dollars or more. If you paid that much for your car, you’d have grounds to expect brakes that can take racing enviornments (and generally, million dollar supercar brakes can).

The brakes.
The brakes are a mandatory component in every car, but must be sized to handle the enormous stress created by high speed. When in movement, a car accumulates a kinetic energy proportional to its mass and to the square of its speed (E = m.v2); stopping it or simply decreasing its speed means that this energy must be transferred somewhere else and the simpler means is to dissipate it into heat by friction in the brakes.
Rear brake - Winston West series All NASCAR cars are equipped with disc brakes, because drum brakes would not be able to sustain the thermal stress. NASCAR authorizes only one pair of pads per wheel, and one piston per caliper.
There is no rules concerning the material to be used. Steel, carbon fiber or aluminum are legal, but in practice and for cost and availability reasons, only steel is employed, sometimes aluminum. No anti blocking system (ABS) is allowed.

source: http://membres.multimania.fr/binuxracing/brakes.html

This is what the racecars use. This is the material you see glowing.


http://www.bing.com/images/search?q=carbon-carbon+brakes&qpvt=carbon-carbon+brakes&FORM=IGRE

@bscar2-

The OP referenced LeMans as an example. This is as different a racing environment compared to NASCAR as the comparison of either race vehicle (LeMans or NASCAR) to a production automobile.

Not nearly as much braking going on in circle racing vs twistys.

Depends, TT. Bristol is hell on brakes.

went to ask.com and asked what race car brakes are made from. that was one of the closest matches it came up with. was going more off shadow’s post than anything

NASCAR tends to stress older technologies. The cutting edge stuff is rarely found on a stock-car.

And realistically, you can have even less durable racing brakes than that, depending on the application. An MR2 can have street-capable racing brakes on it. Carbon-kevlar compound pads and high quality rotors, steel brake lines, and high-temperature brake fluid (dot 5.1 can go 117 degrees F hotter before it boils than the dot 3 you find in many street cars). Why can I consider them racing brakes? Because with that setup, you can run it full out, on a track, for a long time, and they don’t fade or catch on fire.

An MR2 doesn’t need the carbon-carbon stuff no matter what It’s doing, because that car isn’t nearly as fast as the monsters that do, which means it doesn’t have to work as hard slowing down for a corner. Braking from 200+ to 50mph is very, very different stress-wise than braking from 110-50mph.

The important bit regarding this discussion is that the glowing brakes on race cars, no matter what they’re made out of, are still effective and don’t set things on fire because they’re designed for punishment that a street car will never see. Everything from the rotors, to the calipers, to the lines, to the fluid, is all geared toward experiencing much higher temperatures than normal, without losing effectiveness.

Too bad they ruined that track IMHO- It used to be tough on sheetmetal and paint too…