There is a groupbuy going on over at M3Forum on a 4 piston Brembo brake kit for the E46 M3. The kit is 4 piston monoblock and E9x M3 rotors (360mm rotors?).
http://www.m3forum.net/m3forum/showt...594414&page=55
I have been following the thread. Since Z4M and M3 ZCP share the same front brakes, I think the kit will work on our E85 /86 M. The kit will be around $1k. Great price if it works. I'm absolutely no expert in brake specs. Would like to hear your thoughts on this.