i have a 2000 si turbo and im trying to figure out if bigger rotors are better or bigger calipers. stoptech has 4 piston 328mm or hp racing has 6 piston 11.5" for example.

 

un-sprung weight is your enemy, so going with a stronger caliper and smaller rotor (read:smaller wheel/tire combo) will help you out in that department and should stop you easily up to around 130mph without question