Quote Originally Posted by 39PitCrew View Post
This is my somewhat non-scientific observation - I'm sure someone else can correct me if I stray into nonsense land.
David uses the OReally rotors. We were routinely getting more than a year out of them before
they cracked a face. Near the end of life we'd see a lot of surface checking though.

A new rotor is more likely to crack at Hallett due to the extreme heat cycling that happens there.
A rotor that has been work hardened through many less-severe track sessions should be fine at Hallett.
At least that is my observation from wrenching on OiF #39. Also, a big player, again from my
experience with #39 at Hallett, is to make sure you have a nearly new brake pads on the front
rotors so the heat capacity of the pad is a little better (also more pad reduces the brake fluid
heat uptake a little bit I would think).

Just my 2¢.
Well there's your problem, the #39 is your point of reference.