I had 22s on my S before I went back to 21s. 245/30/22 in the front, 285/25/22 in the back.
265 won't fit in the front of a 1st Gen S. You'll rub like mad. Depending on your offset you may be able to squeeze in 255 with a little rubbing, but 245 is pretty much the max width up front without rubbing.