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      12-31-2009, 05:06 PM   #12
Lemans_Blue_M
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Quote:
Originally Posted by lucid View Post
I found his post on this. Here you go, but the OEM 18" rear PS2 is actually 265/40/18, so that might make the difference in terms of clearance. Even with 35 aspect ratio, it would be close with the PS2.



http://www.m3post.com/forums/showpos...postcount=2150
Ahh, now that makes sense.


This explains why he was rubbing on the liners...


The 265/35/18 PS2 tire has an OD of 25.3", and a 265/40/18 has an OD of 26.3" which is a huge difference in tire fitment terms. His 265/40/18 tire was simply too big fit inside the front wheel well. It wouldn't have mattered if they were PS2's or not, that tire size has no chance of working.

A 265/40/18 tire would eventually rub a hole in the wheel liner. The clearances are so tight, that you are limited to 26.0" OD max. (and even that may rub under full steering lock)

The BMW engineers were just stingy with the real estate in the front wheel well.

Now the 265/35/18 mounted to the 18x9.5 +25 offset wheel, will have a lot more clearance to work with...since the OD of the tire is actually 1" smaller.
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