backspacing

USMC_Turbo6

Well-Known Member
Joined
Dec 13, 2009
What would be the backspacing for a 15x10 wheel, or des it depend on the brand of wheel?
 
Depends on the brand and if they put an offset in, the offset moving the backspace in or out. A place like Summit will have the details if you can get your wheel there. 0 offset would be about 5.5" backspace. +25mm offset would be 6.5" backspace. -25mm offset would be 4.5" backspace. Add an inch to width and divide by two to get 0 offset backspace, then add or subtract the offset divided by 25 (its usually in millimeters).
 
A lot also depends on the sectional width of the tire being used- a 12" sectional width has 1/2" deeper width than a 11" sectional width tire- thus could cause rubbing on frame, I measured from the wheel mounting pad to the frame and got 5.5" so the backspacing of the wheel plus the sectional width should not exceed 5-5.25" or I'll be rubbing the frame. If you mount a tire on the wheel and put a straight edge across the sidewall of the tire measure in to the mounting pad and this will let you know what works and what don't.usually as you go up in rim diameter there is usually less sectional or tire bulge due to the lower profile wider based tires. A 15" rim uses less backspace because of the tire bulge- I can use a 17" x 10" rim with a 5" backspace but on a 15" x 10" I would probably only be able to go with a 4.5" backspace.
 
my 10'' wheels are welds draglites with a 4.5 backspacing with cast iron brake drums the aluminum drums push the wheels out i think about a 1/4 inch more and im running a 275/60/15 tire and they fit great!
 
Ok I have the aluminum drums on my car and want to run 295/55/15. They come un a 5.5 back space
 
A 10" wheel with a 5-1/2 backspacing will not work unless your car has a frame notch and a 295-55-15 will not work ether unless you have a frame notch the only thing you can run is a 15x10 with a 4-1/2 backspacing and a 275-60-15 and I'm for sure on that anyone else want to back me up on this ?
 
Look how close my wheel and tire is too the frame and look at this other pic how close it is to the wheelwell lip and that's a 15x10 4-1/2 backspacing with a 275-60-15 tire
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E Brake- do you have any pics of that tire from the outside of the wheel well to see how it fits?nevermind I just saw the first pic- I think I have less tire bulge on my 8" rims with that same tire cause I have more room to the frame. Is that a stock or aftermarket rear axle?
 
That's a stock axel I built 33 spline spool & axels 5/8 studs 9" ends willwood brakes TA cover and braced up and TRZ spring perches
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Very nicely done! I asked cause I noticed the disc brakes, I am currently running a 9" ford rear in one car and a 12 bolt with a 411 spool and 5/8" studs.
 
Yea I wished I'd went ahead and built a faded 9" I probably will later on that's why I put 9" ends and brakes on my rear end so I can use the brakes on a 9" if I put one in my car
 
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