looking to buy a set of 15x8 prostars for the street (gonna wrap them in 275 drag radials) ...

just wondering what backspacing i should get for the 8" wheel ..

 

6 1/4 should sit is pretty flush
they have a 15x8 5.5 inch backspacing listed on their site but i think that will stick out of the wheelwell about half inch. give them a call or email it usually depends on the car they should kknow what to use. if they have a 6 inch that would be closer but they dont list it.
http://www.weldracing.com/Questions.html

 

6-1/4" BS is approx. the stock 16X8 wheel. But you can move the wheels quite a way out without having them stick out from under the fenders. The general preference for 15x8 Weld Pro-Stars is 5.5", and 7.5" on the 15x10's. Both of those combinations place the outside edge of the tire in exactly the same place.

I have the 15x10 7.5" BS, so your 15x8's will sit exactly the same as mine under the fenders. Only the inside clearance to the inner fenders will be greater with the 15x8's.

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