1st to 3rd

This is with a FD that sees regular road course duty using stock brakes and Hawk Blues. Fade/boiling is an issue when pushing hard, but the brakes feel secure otherwise.
I've been having an issue with turning my rotors into a nice dinner plate shape. The outer portion of the rotor is wearing quicker and there is a nice dish shape near the hat. Thermo paint is telling me that the outer edge is exceeding 1400°F, while the inner portion is significantly cooler (didn't put paint on the inner portion, but it's obvious by the rotor's coloration). I am aware the stock rotors are too small for real track duty, but I was under the assumption that the stock FD caliper is a solid piece? Is this normal behavior under this much abuse or is there an issue with my calipers?

DamonB

The FD calipers are not monobloc, they are bolted up. I seriously doubt it's a caliper problem. Sounds to me like you're just overheating the brakes.

The outer edge of the caliper will run hotter since that's where the pads are (hence that's the place you check with temp paint). Since the stock rotor is a single piece once terribly overheated the outer edge expands making the dish shape. This is one reason that in high performance applications 2 piece brake rotors are used with a seperate hat that allows expansion between it and the rotor without deforming the assembly.

1st to 3rd

Thanks Damon. The more I think about it, coning does seem like the more likely answer. Oh well, this is where things start getting expensive.