If you have the stock 15" 15 hole rims then you can only go as Alon said with 205/60/15. Some have gone to 215 but it gets pretty hairy with that kind of width on a 6.5 inch width rim. Your best bet is to get wider rims like the 8 hole OEM or jump up to 16" or 17" rims. If you're thinking of getting new rims later then you might as well wait.