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Front brakes Rear brakes MOV' IT six FAQ Better than stock sport brakes for the Audi RS6 A client's comment about the stock brake. There are some fundamental shortcomings with the stock brakes. Firstly, the rotors are mounted on floating steel pins. This is not unheard of in racing but as implemented by quattro GmbH, it is not ideal for road cars. Firstly, the isolating steel pins trap the heat within the rotors and secondly, the way the design is implemented, there is no way that air can be forced into the centre of the rotors and spun out by centrifugal forces. So as a result, the rotors get very hot indeed, which means that they do not last very long and the transfer of material from pad to rotor is accelerated (this process is commonly described as 'warping'). Why is this design ok in racing and not good for the road? Well, in racing rotors are a disposable, even at Le Mans the cars only travel about 3,500 km, so the logevity problem is not an issue. When Audi is showing off the RS6, you will always see spare rotors in the garage. Secondly, the nice big chunky looking 8 piston brembo callipers look the part, but there is one small problem, the actual swept are of the pads is comparatively small. This results in hot spotting and enthusiastic driving can set the pads on fire. Certain aspects of driving on German Autobahns are tougher than track driving. There are very few raced tracks where you have to slow down from over 300km/h to, say, 30 km/h in a real hurry, mostly in a race environment the brakes remain at operating temperatures, on the autobahn you are often braking hard with cold brakes. I totally destroyed one set of stock rotors in one Autobahn trip of less than 400km, I wasn't particularly hurrying, I was going out for dinner with friends and I had to cope with the remnants of evening rush hour traffic, nevertheless in three hard stops I completely destroyed the rotors, total milage on the car at that time, less than 1,600km, most of it in areas with enforced 120km/h speed limits. Now the first question people ask is, do the 'sport' brakes from quattro GmbH help. Answer, well some but not much, these are the same rotors but cross drilled and different material pads. Remember the way the car comes from quattro GmbH (and Audi AG), most of the braking is done by the front brakes because the design of the rear brakes, with their integrated handbrake function, means that the rear pads are so hard that they do very little work, so you are still doing a great deal of braking on the front axle and not a great deal on the rear, despite it having a greater capacity for doing so than most other Audis as the weight transfer to the front axle is not as pronounced thanks to the DRC system (when braking hard the nose doesn't dip like most cars). In the longer term, look to quattro GmbH changing rotor material, but it won't happen any time soon so don't hold your breath! Switching to Movit brakes front and rear provides excellent braking performance, but is still tough on even 380mm rotors, the retardation is better than it would be with PCCBs. A colleague who has an extremely highly modified 959 ClubSport (without all the comfort junk) is so impressed he is switching to a similar brake setup, that is some compliment. Good brakes are not cheap, which is why so many manufacturers fit such awful ones!
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