[ChevyThunder]

The rotors at the rear are smaller because you don't need as much brake at the back.. my race car has 15" rotors with a Brembo Endurance Caliper up front... at the rear I use 14" rotor with the same calipers a Ferrari F 50 uses up front... during a race the bias will get adjusted to compensate for changes in braking due primarily to tire conditions...