[Christian1LE]

Is there a certain rotor width percentage that I should be looking for or do I just keep monitoring the heat cracks? When the heat cracks reach the center hub is it time to replace?

Trying to get a gauge here since I've never had to replace rotors before due to track use. I've just been seeing that my heat cracks are getting more and more pronounced.

[RamAir02]

You should literally get a gauge

This post from Arpad has the minimum rotor thicknesses

[NinthWave]

I don't have much track use on my SS1LE yet, but have been through lots of rotors on other track cars. I have never reached min rotor thickness on a track car, have always tossed due to cracking. (On Porsches the thickness limit is -2mm from new, or 1mm per side. There would usually be a distinct "lip" also.)

Clearly cracks that reach the inner or outer edge, the rotor should be tossed. Unless you are carrying spares and prepped to change at the track it becomes a judgement of whether the rotors can complete an event. I tend to be conservative- if there's a doubt, then there is no doubt.

I found this useful for general background- https://www.essexparts.com/news-blog...-my-iron-discs.

Hope that helps

[kropscamaro16]

when they start to have cracks you can feel with your nail my oem rotors lasted 2 years just replaced them with giro disc rings

[cdrptrks]

Originally Posted by RamAir02

You should literally get a gauge

This post from Arpad has the minimum rotor thicknesses

Note that the post from Arpad highlights a different rotor size with a different thickness although the correct info is there. The SS 1LE comes with J6M brakes by default. The fronts are 370mm diameter with 34mm thickness when new and 32mm discard thickness.

The SS 1LE copper free brake option comes with larger 390mm J6H front rotors. It was introduced for the 2022 model year as a requirement for California and Washington State and an option for the other 48 states.

Or you can save money by notching a $10 plastic digital caliper from Harbor Freight with a drill bit or Dremel as pictured below. In my case the rotor cracks were on the inside by the hat bolts and they were not visible from the front of the rotor until they got bad. You can see 1 example picture in this post and 2 more if you scroll up to the previous post: https://www.camaro6.com/forums/showt...8#post11147668

[Christian1LE]

thanks everyone, very helpful

I'm at 33.5mm so I do think the cracks will get to me before the rotor thickness goes. I always inspect to see what the cracks are doing. I suspect I'll have to change them after about 8 more trackdays.

[cdrptrks]

With stock pads, the heat checks never became cracks for me before I hit minimum thickness. Higher torque pads might make the rotors crack sooner though.

[5.M0NSTER]

Good thread, thanks for posting this. This made me check my rotors as well. So after 6 track days, wearing DCT60s daily, total of 12,000 miles on the car (6k wearing hawks) I was at 33.53mm. Happy with that.

[GunMetalGrey]

I run Hawk DCT 70s, on the street and track, I have very little in terms of heat cracks but the rotor thickness was below minimum when I finally checked, So yes I think higher torque friction pads really wear down the rotor especially Street driving when they are cold

[wakespeak]

I have heat checks after about 3k miles of track use. New rotors in the garage, but measuring the old ones makes sense. Let me order that!