I am planning on putting 12" rotors onto my '88GT and want to keep the 15" lace wheels. The rotors can be squeezed into the rears, but simply will not fit under the fronts.
So I am considering putting a set of rears onto the fronts (actually wheels from an '87). This looks a lil odd (I got to see it because my tire shop screwed up when I had new tires installed), but it is better than playing "find the right wheel and then buy new tires to match" game.....not to mention a LOT cheaper! I think it would look less odd if the rears were spaced out like the fronts will be.
Which brings us to: what thickness 5x100 hub centric 57.1 pilot hole spacer do I need on the rear?
Now, it appears (from other posts) that the 88 GT and Formula used lace wheels of the following sizes: Front is 15" X 6" with +37mm offset; Rear is 15" X 7" with +30mm offset (same wheel as the one used on all 4 corners of 86-87 GT).
So, using an '88 rear on the front moves the outside edge of the wheel outward 1/2 of the increase in wheel width plus the 7mm difference in offset. That is about 20mm. And putting a 20mm spacer on the rear would move the outside edge of the rear wheel out to match.
