I have 275 35 18 eagle f1's and they are fine, the tyre diameter is slightly larger so going for a 285 may make the diameter a bit too big? I also have some 295 30 18 track tyres and the diameter of those is slightly less (probably about 10mm) than a standard 265 35 18 tyre.
I ran 295/30/18's 048's loved them but they were a smaller rr than the stock 265's.... I decided to go back to stock 265/35/19 which still provide same traction so see little point going bigger (and thus heavier) anymore.