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Discussion Starter #1
I just bought 2 1999-02 style camaro wheels. They are 17x9 inch rims with 275-40-17 BFGoodrich G Force TA tires. There is no rub on smooth roads and a slight rub on this real dippy type road. The rub was on the passenger side. I would have thought it would rub on the driver side. The tire is the same height as the stock 245-45-17. The tire is also in the same spot as the stock size tire so how the heck is it rubbing. The extra width seems to be inboard. I had an odd sized 235-55-17 inch tire which was 27 inches tall and clearly was wider and taller then the 245-45-17 inch tire with no issues. The road that the tire rub occurred on was a 35 MPH road. I was going about 50 around the turn that had the dip. So technically speaking if I drive the car at the posted speed limit, there is no tire rub. No tire rub on launch but to much tire spin. These tires are not that good at hooking. I was thinking of machining 5 mm off the mounting surface to bring the rim inboard more. I must have at least 1 1/2 inches of clearence on the inside. I will be replacing the wheel studs with ARP studs and rework the 120mm bolt pattern to 120.65 when I get in touch with the company that does this. Any thoughts on this are welcome. Coil springs are new from the dealer and sits about 2 inches above the tires the shocks are stockers so im sure they need to be replaced---------Danfigg
 

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Remember that when the wheel compresses upward it also tips in at the top so you can't tell by static observation. The best way to see what's going on is to remove the bottom bolt on the shock and remove the spring. Then you can move the wheel through its entire motion. Tires wider than recommended for a 8" rim causes the tire sides to bulge and makes it wider than if it were on a wider rim.

Another factor is the inner and outer control arm bushings. They can allow the arm to move its two pivot points especially with lateral forces like turns. The inner one in particular has big voids in it to allow movement. Replacement with fixed polys fix that.

You can kind of see the voids in the bushing and the tool I made to remove them (with added heat). Inner bushing is on the left, outer on the right.

 

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Discussion Starter #3
re

I did think of suspension travel in all this but didnt think of the bushings I do know the rim has a 6.98 offset. I would imagine if the stock GTO rim had less offset that that tire would rub the quarter as well. 7.05 inches of back space should move the rim inboard enough to clear the quarter. Then the inner quarter would probably be the next clearence issue. Thanks for the insight SVEDE
 

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I run a 285/40/17 on a 9" (widened) stock 17". I had the same thing on cornering and the bushings were the last piece of the puzzle that fixed it. Good luck.
 
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