Crack whores - Part II

Well, it's happened again; not as bad as last time, but the Project μ SCR Pro rotors are still cracked nonetheless. After two track days, cracks developed from the holes where the rotor bolts on to the hat. Then on their third track day at Sandown, I could feel a vibration through the steering wheel under hard braking. The uneven surface around the cracks also took small chunks off the edges of the brake pads.

This is the left rotor with three noticeably large cracks. The right rotor also had a couple.

Close up view of the cracks:

From inside the rotor, you can see where the cracks started.

The rotors had only worn down about 0.25 mm and they still performed fine on the road, but with more track days coming up I had to replace them. Instead of paying a premium on a brand name rotor again, I decided to try a set of rotors by X3E Motorsports. These rotors are apparently hardened and more resistent to wear, lets see if they can withstand cracking. Thanks to JimJim for recommending these to me as he uses a set on his Evo.

They weigh around 7.5 kg each, so they are roughly 500 grams heavier than the Project μ. As a comparison, these are the weights of other rotors:

DBA 4000: ~8 kg
DBA 5000: ~7.5 kg
Project μ SCR-Pro: ~7 kg

I'll also be working on my cooling for the brakes to mitigate the effects of hard braking on the track.