ZOO
Dork
4/11/10 2:23 p.m.
Reviiewing my brake work from yesterday, and I noticed that I received two rear rotors that are the same (should be a left and a right side). The only difference is the direction of the vanes. How much should I worry about this? For the rear of the E36 M3.
Rob
Are they SUPPOSED to be different part numbers?
Every Turbo Coupe had two "left-side" rotors.
some rotors have curved vanes, if the wrong one is installed it restricts air flow as it is designed to optimize the air when mounted the correct way, check with manufacturer IMHO
If you don't track the car it probably won't make any difference. However if you track it get one swapped out. Once the rotors get warm enough for the directional cooling fins to make a difference you will get different cooling between left and right. In the extreme this could cause rear braking problems (un even left vs right) or just cause one side to over heat the pads and wear faster.
My 944 spec runs straight vane front rotors, but I have cooling duct to the left side and not duct to the right. The reason is that I replaced a brake duct hose with an oil cooler. So I just put an air turning plate to capture some air. Not sure if it works. Braking performance is fine, but the right side does use more pad and I can see the it also get hotter based on the temperture on the pads. I typically replace my pads when white "hot zone" gets to the backing plate.