Autocross/Track Duster Wheel Help

DSTR 340 said

That’s awesome that’s exactly the kind of information I was looking for. I will take your advice and go with 18x9.5 over 10. Can you just clarify what offsets i should order for the front and back to keep it the same all around. The car is setup with its original Abody 8 3/4 that i changed the axles to the BBP. I get a let lost when it comes from 35mm to 8+

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The "problem" with A-bodies is that the track width is not the same front and rear. That's especially true with 73+ disks up front and an 8 3/4 out back. You can't really run square and rotate your tires with that combination, because the wheel offset needs to be different from front to rear.

In the front, with a 73+ BBP disk brake set up, an 18x9.5 with a +30 to +35mm offset will work. That's the same as saying an 18x9.5" with 6.4" to 6.6" of backspace.

In the rear, the 8 3/4 is too narrow for that much backspace with the stock spring locations. Typically with an 8 3/4 and BBP axles you'll only have about 6" from the wheel mounting surface back to the spring. With the 6 link you'll have a little more room, but still I don't think you'll be able to use much more than 5.5" of backspace, which is only a +13mm offset on an 18x9.5".

That's why a 68-70 B body rear housing comes in handy, because it makes the offset (or backspace, whichever you prefer to use) the same for the front and rear. So you can actually run the same wheels and tires in the front and back and rotate your wheels.