That car had the AP Racing kit, but we have since started using our own combination that is more price effective. We use Wilwood
calipers, pads, and rotor hats. Custom rotor blanks and
caliper mounts. Either kit works fine with the
OE master cylinder, but we delete the booster in all of our cars, so I can't comment on how it will feel with assist. Sometimes we will play with the MC size to get the right feel, but that is dependent on the driver. Not all of our cars run pedal boxes, just depends on the level of the build. But, we ALWAYS upgrade the brakes.