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Old 05-22-2007, 06:03 PM
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540cmc 540cmc is offline
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Location: Orlando, FL
Join Date: Oct 2004
Posts: 196
Mein Auto: 2001 540
Originally Posted by Fulltone74 View Post
Hi all:

Question is this: is 255/40/17 too much tire for a 17x8 wheel. The service tech at the dealer said that having an 8" wide wheel makes the sidewall bow in a bit where it mounts to the wheel. He said that this bowing effect makes the tire sidewall easier to compress and could compromise the steering response of the car.

Given that, I would think that if I stayed with my existing wheels, the car might actually feel better with 235/45/17 in back. Would you all agree with that?

Otherwise, the next best choice would be to go to the M-spoke 66 wheels to have 17x9 in back.
The 255/40/17 will work just fine on an 8" wheel. I have run that size all around on a set of style 66 wheels (8" front / 9" rear) as my autocross set up for two years. With Falken RT-615s, the steering response was just fine and handling was much better than with the stock 235/45/17s up front.

I agree with same size all around if possible for better handling, however, I would go with the 255/40/17 all around over the 235/45/17 all around. Same size all around dials out some of the E39 understeer, gives better balance and larger is better in my opinion.

With that said, what you really need to do is buy the staggered Style 66 set I have listed in the classifieds for sale!
AFE intake, Stage 2 Dinan software, M62 intake, Dinan trans SW, 3.64 limited slip, Michelin Pilot Super Sports 265/35/18 all around on 18x9 Style 37 wheels, SuperSprint headers, Magnaflow 3" exhaust, Dinan Springs, M5 rear sway bar, Dinan strut bar, SS braided lines, Technical Graphite interior trim, M5 deadpedal, Titanium Silver / Grey, Black side moldings, M-Tech rear bumper, debadged.
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