Re: wheels size
On the front, the 18x8 with a 4.75" spacing is okay, but I usually run just a hair more if possible, on a lowered car, like a 4.875 or 5". For the rear, the 3.75" backspace is the min on most custom built wheels like Billet Specialties, however, it puts alot of the weight of the wheel to the front, which is NOT good for axle bearings, etc. Which is why we, and other companies like Detroit Speed prefer to put the backspace (and the center of the wheel) closer to the center of the hoop, in most cases a 5.5" backspace on a 13" wide wheel. You'll still get your nice DEEP wheel, but function must dictate form, and from an engineering stand point, this will work better. And, on a 13" wide wheel with a 5.5" backspace, you'll still have 8.5" of front space.
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