>I believe the big brake kit comes with larger rotors and a
>caliper relocation spacer.

yes.

>Larger rotors will give you a
>longer moment arm from your pads to the center of rotation
>which gives you greater stopping power.

yes.

>Larger pads would
>arguably help as well, but contact area has never really
>been proven to affect friction. Friction force is
>determined by the normal force (piston) and the coefficient
>of friction (metal rotors to whatever type of pads you use).

Yes. Main benefit of larger pads is that they manage heat better, AFAIK.

>anyways, enough theory. I think you can see the big brakes
>will help you stop faster even with the same pads.

I have the AEM FWD kit, front and rear. The biggest gain is the better braking modulation ability. It is much easier to hold things at impending lockup, and thus minimizing stopping distance.

For track purposes, the extra mass of the larger rotors will also delay the onset of brake fade. The cost of course is an increase in unsprung weight.

juan