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Mismatched Wheel Widths

333 Views 6 Replies 5 Participants Last post by  ProZach626
The specs on my OEM rims are 18x8.5 and the specs on my new rims are 18x9.5. So far only two of the rims have arrived, and I want to install them on the front instead of waiting for the other two, but I’m going to be running a small stretch. The tires I have on my 8.5 OEM rims are 245/40s and the tires for the new 9.5 rims are also 245/40s. I’m not sure how big of a difference it would make, or if it would be enough to harm the internals of the car since there would be a slight change in the complete diameter of the front wheels compared the to rear wheels.
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This again?

Sidewall = 245x0.4 = 98mm
Radial difference = 98 - root(98^2 - 12.5^2) = 0.8mm
Diameter difference = 1.6mm
Subaru diameter diff limit = 2/32" = 1.58mm
By the time you get your remaining wheels, there will be more wear
= yes it will fuck your transmission.

Also, just why? Stretched tires have no performance advantage and 9.5 is a stupidly wide wheel for this suspension. What's so urgent about this that you can't wait for remaining 4 wheels?
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