rim sizing 18" - how big can I go?

[lagvoid]

For an E36 M3 (1997 if it matters), what tires should I put on 18" rims? I do not want to remain with the staggered setup and I would rather go up in size. I know 245 all around is fine, should I go any bigger?

[SilverStreak]

245's all around will probably be the largest you'll be able to go with 18's, with proper offset for the fronts to avoid rubbing...