Originally Posted by mastek
This is not right -- you either have defective parts on your BBK -- or your pads are defective -- or your fluid has air in it -- or your ABS pump is wrong -- or your brake booster is wrong.
I would start another thread and bring this up to AP Racing -- I have had Brembo's (e36m3), StopTechs (e46m3) and now AP Racing ...and the AP Kit is most consistent and has the best pedal feel of all 3 IMHO. You should be raving about the consistency and predictability of this kit, otherwise something is wrong.
It is the brake boost assist. This happens to fast drivers in the E9X M3. The system pulls vacuum from anywhere it can and you get an inconsistent pedal.
AE performance is working on a fix for this. It happened plenty of times in my car, happens with their car as well. Anyone driving fast knows about this.