soloIIracer squeezed a 285 on the FRONT stock rim with a 1/4" spacer. He was at stock ride height and as far as I know he didn't have interference problems. The suspension bolt limits you on the inside meaning you know what. You can fit a 255 on a lowered xfire with the perfect offset, lots of negative camber and a little fender rolling and have it tuck inside the fender. A 285 wont tuck no matter what you do so the car has to be at stock height with the tire sticking out.

The rear can handle a 295 I believe. I've used a 285/35/18 before.

Les