[TurboBimmer]

Originally Posted by radiantm3

I can attest to that. I guess I just worded my previous comment wrong. I meant braking performance in general and that means at the track as that's the only place where aftermarket brakes will become useful. My stock brakes stopped just as well as my brembo 380 kit. The difference is I can run 25 minute sessions throughout the day in 100+ degree weather without a hint of brake fade.

My biggest fear at the track is having the brakes not working properly when slowing from 125mph to 30 around a hairpin turn with a wall straight ahead. Going from the 365 to 380 kit is just a tiny fraction of the cost of the whole kit so why not get the one that will most likely stand up to heat the best. At least that's my thinking.

Bigger discs will limit the choice of wheels. Not many 18" clear the 380mm kits.

Stopping power will indeed be virtually the same and heat dissipation a bit better with bigger discs. But even the "small" 355 or 365 BBKs will outperfrom any stock setup by a large margin.