Backspacing for 18" wheels on 91 coupe

clang said:

I have a 91 coupe that I am starting to do a 5 lug conversion on. I like the maximum motorsportrs 18x8.5 wheels but am trying to decide on which offset to get, they come in 15mm(5 3/8 backspacing) and 36mm (6 1/8) they recomend the 15mm offset for the fox but I am not sure if that is enuff offset to keep from rubbing the fenders. I just got some 95 spindles so I will probably be using them but I haven't bought my axles yet so I could go with sn95 axles or fox lenth depending on witch wheels I go with. It seems like a lot of the wheels that I see on the fox's have more than 15mm offset. What do you think, are the 36mm ones going to rub on the inside of the front or rear? It seems to me that the 15mm ones are not enuff and the 36mm might be too much. I do have Steeda sport springs so the car is lowered a little bit. Thanks for your help

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The larger the offset, the more the wheels will sit in the well of the car. The smaller the offset the more the wheels will sit out toward the curb.

If you use 94-98 axle shafts you are going to want to use the 36mm offset wheels for the back. You might have to ditch your quad shocks with that offset and being that the wheels are 8.5" wide. No big deal though, just get a set of LCA's. Brand doesn't matter. I have 179 dollar UCA and LCA kit and they are just as good as my pricey UCA and LCA kit from HPM.

If you use 94-95 spindles, your stock wheels will be pushed out 5mm. A stock Mustang 17X8 wheel has a 30mm offset and still sits inside the fender. Those wheels are 18X8.5 so I would order the ones with the 15mm offset for the front. They are gonna be pushed out right to the edge of the fender. They might even stick out a few millimeters depending on the tire size. The 36mm offset wheels will fit the front too, but with all that backspacing, they may hit the strut. That sucks they don't offer them in a 24-30mm offset. 15-30 is too big of a jump. (Don't use 94-04 spindles with those 15mm offset wheels....they widen the track with 8mm more than 94-95 spindles for a total of 13mm.)