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Old 03-26-2007, 09:38 AM   #20
Rob Levinson * UUC Motorwerks
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Originally Posted by jpr View Post
Does that include the ZCP rotors? Are the ZCP rotors the Euro/CSL version?
Yes, the 345mm front rotors are identical to CSL rotors. The 325mm front rotors are standard M3 Euro. The 328mm rear are common to CSL/Competition Package/Euro.

What do you make then of the proscription on machining the "M" rotors? Is the terms "M rotor" BMW code for floating rotor, or is there something special about even the 1 piece rotors that prevents them from being able to be machined?
I would think that it has to do with the same "commen sense" concept against machining any BMW rotor, that the allowable wear depth is very small... and considering that the Motorsport applications are expected to be used more aggressively and see higher heat ranges, it's simpy easier to say "Nein, machining verboten" than to say "Das machining ist für Dummköpfe!" and get into a whole discussion about it.

I suspect that the TIS uses "M rotor" to mean floating, but cannot substantiate that beyond a qualified guess.

- Rob
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