I ran P255/60R15's in the back with the only issue being one side rubbed when the car had a lot of weight in it (like 5 offensive linesmen worth of weight).

Other than that, no problems. Never tried that big a tire in the front. 87 Diplomat.

They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.