What I'd like to find out here centers around the brake caliper pistons.
The aluminum pistons in the 135i charcoal-colored pistons don't seem adequate for HARD track use. We are having trouble with them as they don't seem to be holding up very well.
Are the pistons in the yellow calipers made of a different material - like steel maybe? I heard the piston material is different.
Will the pistons in the "Performance" kit fit in the charcoal calipers? Can those pistons be purchased separate?
Evosport is thinking about making or finding replacement pistons that will fit in the charcoal calipers.
-Ralph
PS. If anyone from BMW is listening here... connect with me at
ralphwarre@yahoo.com I have some very interesting information for you and Brembo about the aluminum pistons. We've raced the 135i and lets just say - they are not holding up well - and we are concerned about the safety of others who take the 135i on the track.