I would like to run a 12" in diameter with either an 18" or 19" rim. The taller the tirer the better. Any suggestions on what combo to use to fill up the entire space?
Nitto NT05 on my car. The rear was 335/30/19 and it was the 27' that Ron stated. I had it on a 19x12.5 rim and it fit perfect. I also slightly widened the DSE tub and had no rubbing issues.
level. I set the car up to have an inch or 2 of rake, since I think 1st gens look better with a little rake based on the roof line. I liked the look of the 18's in front and the 19's in rear.
As far as rubbing, plenty of 69's have been done with the 335 in the rear without rubbing. You will need to trim the lip back on the quarter for sure. Different tire manufacturers widths are different. In the case of the NT05, it is a wide 335 and I had it on a 12.5 rim that made it that much wider. You figure rim was 12.5 at the bead so overall it is 13.5 plus a little bulge on the tire and you are at 14.00 to 14.5 worth of rubber to to stuff up in that opening.
On the front I ran 18x9.5 with a 275/35/18 front tire. Had i kept the car I would have gone wider in the front, but my car was different than most and I had a ton more room I could have used.