| I've never seen brake disks (rotors to you americans) warp from high speed braking. My 318 E30 I did two crash stops from 120-or-so in quick succession. The first was fine, the stock solid disk brakes were fading a little one the second. These were about 3 miles apart (the idiot in a merc e-class pulling out in front of me, and suddenly pulling off without indicating)
The damage from this was all 4 brake pads (cheap-ass Jurid pads) failed - cracked.
One subsequently blew it's surface off, causing total brake failure - that was fun!
Anyway. I know you can warp them through overheating, which isn't mch of an issue with one stop from 120. Racing hard on a track I would expect serious brake fade before the disks warp.
The main cause of warping I find is people coming into the pits after racing on a track day and holding the footbrake or handbrake (emergency brake in america?) on as the car sits for a few minutes. This means the disk cools unevenly.
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Unmodded (and never will be) E30 318i | 
