'88's have rubbing problems with the skirts. Go just a bit smaller diameter, 245/40R17Thanks again for the info. I seem to be in the ballpark with what I was thinking for gears 3.55, 3.73. 3.73 seems to be more common. As far as tire size 245/45R17 (25.7") cold air intake, better exhaust, better intake(?) - nothing dramatic.