Guys, I need to purchase some wheels for a set of 28 x 9 Pro Drag Radials I acquired. What BS would I want for an 8" or 10" wheel? (72' Skylark) Thanks
4 1/2" BS on an 8" wheel is the minimum. I have that on my 15 X 8 reproduction Rallye wheels. It is very close on my driver's side, but the passenger side has great clearance. It isn't unusual to have more clearance on one side because the frame isn't exactly square to the body. This becomes even more critical on a 10" rim. BS on a 10" rim is 5 1/2" minimum. On an 8" rim, I'd go 5" just to be sure.
As Larry has said, not all rears are perfectly centered. I’d measure yours before buying 8 inch wheels with 5 inch back spacing. If the mis alignment is severe one side’s tire clearance to the frame could be paper thin.
Usually true, except................if the rear is badly off-center and you install the 295/50 x 15 BFG Radial T/A on a 15 x 8 wheel with 5 inch back spacing. It rubbed the frame slightly on hard turns on my '71 GS a few years ago.
I had a pair of 15 X 8", 5" BS wheels on order from Wheel Vintiques for two years when they cancelled my order and refunded my 622.18. My 15 X 8" wheel with 4 1/2" BS were rubbing on the outside, on the driver's side, on big bumps. I solved that by shimming the rear springs a bit, so I am good now. The plan was to use the 5" back space wheel just at the left side rear, one for my street tire, one for the Drag Radial. Luckily for me, I resolved the problem. Car has a bit of rake, but I like it.
That is the standard back spacing for a 15 X 8" wheel, and yes, it will work. My 275 tires are a bit close on the driver's side, but easily clear on the passenger side. It isn't unusual to have less room on one side because the body is not EXACTLY square on the frame.
All these dimensions put the rim closer to the outer wheel well lip on our cars. To have a 15x8 wheel centered in the wheel well, the rim is 9 inches wide. 5 1/4 inch back spacing centers an 8 inch rim in an unmolested 1972 GS 350. Face of drum to frame rail is 7 1/4 inches, face of drum to edge of wheel well lip is 5 3/4 inches. I know the standard 15x8 and 15x 7 work just fine. Im running 5.5 inch back spacing on my 15x8 rims for my 275/50/15 drag radials.
That's correct. I tried to get a set made with more back spacing. I ordered 2 wheels from Wheel Vintiques with 5" back spacing. They made me wait 2 years after I had paid them to tell me they were no longer doing custom orders. They returned my money. https://v8buick.com/index.php?threads/wheel-vintiques-has-been-sold.386942/