Oversized Tires on 88 80q

[River6822@aol.com]

I recently purchased new tires for my car and in my infinite wisdom, I got 
the wrong size. They are 205 60 15's, I wanted 50's. They fit fine in the 
front, no rubbing under any conditions. They do, however rub in the back 
under a heavy load situation.   Situation being an adult in the back seat and 
hitting this large "dip" in the road.  I can't tell where the rubbing is 
occurring. It doesn't seem to leave marks on the tire (either sidewall) or 
the car at all. I think the outside wall of the tire might just be touching 
the little lip on the fender, but I'm not sure. 

Any suggestions would be greatly appreciated.

River6822@aol.com
88 80q