If you put a really wide tire on your rim, you'll have to run less psi than stock to maintain a contact patch with the road. The tire does tend to mushroom out and as a result the middle wears much faster at the same psi as a narrower tire designed for the rim. I myself (with the help of 2 coworkers) managed to wrangle a 295/50R15 tire on a 15x7 Camaro RS rim because the owner insisted on having a monstrously wide tire. It bulged like crazy and rubbed around corners and bumps as well as looked crappy. Also remember there's a reason why there's quad shocks on a mustang....they didn't always have them and the rears would hop like crazy even with the stock traction bars ('82 and '83 i believe had them).
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'84 Mustang 5.0 LX
My car
[This message has been edited by 84stangLX (edited 06-11-2001).]
[This message has been edited by 84stangLX (edited 06-11-2001).]