[justpete]

Read through this thread before i picked up my car when new, and several times since. But in trying to find a better braking solution for tracking the car I've found the 135i front rotors and calipers with Stoptech pistons, boots, and seals work incredibly well with Hard Brake titanium shims and F30 shields when using XP10 pads and Torque RT700 fluid.

The rear caliper doesn't need to be upgraded at all, it's fine as-is with the exception of replacing the guide rod bushings with solid brass parts. Personally I don't think the brake lines matter at all but they're currently Stoptech fwiw.

With Toyo R!R tires the brakes provide more torque than the tires can transfer to the track via slip, they'll skip first. And the pads don't overheat. The car is light enough and not overpowered so this seems to be a great solution. Will be trying RB front rotors but with different pads, eventually, but it's hard to imagine a better solution than what's on the car now. And every bit of it is a simple drop-in without modifications to the e-brake, etc.

As a side benefit the brakes work perfectly on the street summer or winter without eating the rotors although the squealing can be a bit annoying if not used with a soft touch. Not that I care but it is kinda unavoidable.