Cross-drilled rotor warping

[motorman]

read this,these guys do race brakes for a living

StopTech : Balanced Brake Upgrades

 

[darkstar]

StopTech : Balanced Brake Upgrades

Great article. Thanks. ( I believe that is what Hib was trying to tell me as well).

 

[Hib Halverson]

There are a lot of cosmetic brakes on the big time race cars, including the new GT2 C6R, which has J shaped slots on their steel rotors. That said, slots, and especially holes on street cars are for looks, and in competition, holes are problematical because of the cracking issues.

On street cars, which see normal street, aggressive street or even occasional racing duty cycles, rotors with holes or grooves (slots) are strictly cosmetic.

As for holes being "problematical" (actually the word is "problematic") it depends on how the holes were drilled, the design of the rotor into which they were drilled and the material of which the rotor is made.

Let's say you pull the stock rotors off an early C4, set them up in your drill press and put holes in them...yeah, those rotors will fail and, most likely, pretty soon. On the other hand, rotors which were designed to be drilled and had the machine work done properly are unlikely to experience problems related to the holes.

As for race cars, such as the aforementioned Porsche and Corvette C6R applications, if the duty cycle is competitive professional road racing, where brake temperatures are far higher (like the rotors glowing red) than experienced by any production-based, there may be a performance advantage in drilling as a way to reduce the effects of brake pad outgassing.

 

[catbert]

As for holes being "problematical" (actually the word is "problematic")

As for race cars, such as the aforementioned Porsche and Corvette C6R applications, if the duty cycle is competitive professional road racing, where brake temperatures are far higher (like the rotors glowing red) than experienced by any production-based, there may be a performance advantage in drilling as a way to reduce the effects of brake pad outgassing.

Correcting forum grammar is a mark of mental incontinence.

Actually, many of the heavier cars, such as the C6R GT2 do not use holes. Slots must do the job of dealing with outgassng without drilling. I never noticed J slots until recently.