I too want to go wider and have done the homework. Go with a 305/30 which is rather expensive but will fit better than a 315. Granted, it's only 10mm but evidently it makes a difference. like the other guy said, 315, depending on brand and to me, 305 in any brand. I will probably go with a 315/30 in a drag radial myself although I am going to be careful not to make it look to balloon like....know what I mean? There was a post last week with a guy who has many pics of his with Nitto 315s. Look it up. Personally, i will go with BFG.