back spacing for 275/60/15 MTdrag radial

[Lee Thompson]

What would be the correct back spacing for a 275/60/15 MT drag radial on an 8 in. wide wheel? Would 3.75 be enough without having to trim the outer fender well trim ? Thanks

 

[blckgnx]

backspacing

Hi Lee, I just put mine on yesterday. I have 8" wheels (Riken) with a 4.250 back space and everything is real close, but clears. The stock wheels are 3.75 and clear very easily, but are only 7" wide. I have not done anything with the inner lip of the fender either, all stock. Hope this helps, Ron

 

[Lee Thompson]

Thanks for the reply

So if I use an 8 in. wide wheel with 3.75 back spacing--that means that the extra 1 in. (stock being 7) would all be toward the outside. Can you tell me if that would clear. Don't mind triming the fender lip some.

 

[Heath]

It depends on the shape of your springs. Mine would clear fine till I hit a good set of railroad tracks. I would roll the inner fender just to be safe.

 

[blckgnx]

backspacing

Hi Lee, Just went out and checked mine. 3.75 would put you pretty close! My springs are pretty good, but if it sagged very much, you'd be in trouble with the extra offset. Like he said above, Roll the inner fender lip and you'd be home free!!

 

[jasjamz]

Hi Lee, I just put mine on yesterday. I have 8" wheels (Riken) with a 4.250 back space and everything is real close, but clears. The stock wheels are 3.75 and clear very easily, but are only 7" wide. I have not done anything with the inner lip of the fender either, all stock. Hope this helps, Ron

You wouldn't happen to have some pics would you??

 

[Lee Thompson]

Thank you

Thank you for your trouble. I may go with a 4.5 backspacing and shim out.

 

[bad V6]

I have 4 inch backspacing on my 8 inch wheels with those tires, and have not touched the fender well. They only slightly rub on the frame if the rear suspension gets in a bind when crossing an uneven surface. This is with the stock springs.
Pat

 

[wbrophy]

From what I have seen on stock wheel openings and on my car the backspace should be half for the best fit or centering the tire in the wheel well, i.e. 3 1/2" bs on 7" rims, 4" BS on 8", 5" on 10's, etc.

 

[blckgnx]

back spacing

Cool formula you got there, it seems to work pretty good. My stock wheels were 7" with 3.275, and my M/T's on an 8" wheel has 4.250 backspace and fits perfect! I'll have to remember that. Thanks, Ron

 

[KevinB]

Thank you for your trouble. I may go with a 4.5 backspacing and shim out.

Lee, I have 28x10.5x15 M/T slicks on a 15x8 wheel with a 4.5 bs. My car is lowered and I have no issues clearing the frame or fender (and my fender is not rolled.