Author Topic: wheel backspacing  (Read 344 times)

Offline sawdawg

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wheel backspacing
« on: November 18, 2018, 05:01:49 PM »
If I measure from the wheel mounting surface to the roll cage sheet metal I get 8 inches
I borrowed come wheels from my neighbor and the tire bulge was 1 inch (That is the tire bulges out one inch from the edge of the rim)
If I use a wheel with a backspace of 5 inches I get two inches of clearance between the edge of the tire and the body
Is two inches the right amount or should I try for less?

8-1-5=2

Offline rooman

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Re: wheel backspacing
« Reply #1 on: November 19, 2018, 05:02:43 AM »
I like to run mine as tight as possible. My frames are generally narrow at the lower rail than at the shoulder hoop --more like a Woody than a Long- so any air space is magnified by that factor. I generally shoot for 1/2"  at the closest point. If you look at photos of cars from back in the late 60's/early 70's they are generally in that range and some of them have the scuff marks on the side of the body from when they got sideways to prove it.

Roo
Yeah, I am from the south--any further south and I would have been a bloody penguin.

Offline wideopen231

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Re: wheel backspacing
« Reply #2 on: November 19, 2018, 06:50:32 AM »
Ever have any rubbing issue with 1/2" space. Asking because I have spacers on mine to get 1" and no problem removing them if 1/2" will work,heck cheapest weight reduction I have gotten.LOL
Relecting obama is like shooting right foot because it did not hurt enough when you shot left foot

Offline THE FRENCHTOWN FLYER

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Re: wheel backspacing
« Reply #3 on: November 19, 2018, 06:59:19 AM »
As rooman alluded to, the biggest hindrance to running them tight to the body/frame is from turning. My cars have the paint worn off from getting crossed up, where the tread is pulled inward against the bodywork. At five or six psi in the tires it doesn't take a lot of lateral G's to move the tires an additional inch inward.

Offline Roger

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Re: wheel backspacing
« Reply #4 on: November 19, 2018, 08:43:00 AM »
Here's what the rub looks like on my altered with a 1/2" static clearance. Only way to get the tire to touch the frame is to turn a corner at speed, like turning off onto a return road. This is with 7 psi in the tire. Like the Flyer said, it don't take much lateral movement for the chassis to contact the sidewall.

Offline 225digger

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Re: wheel backspacing
« Reply #5 on: November 19, 2018, 09:26:54 AM »
watch your back spacing and wheel diameter, some wheels with deep back spacing you cant use drag brakes

running a shallow wheel will mean a shorter axle, which means less weight {if no one mentioned it}

some guys dont like them but many use a spacer if its alittle to close for comfort.

Offline wideopen231

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Re: wheel backspacing
« Reply #6 on: November 19, 2018, 10:51:32 AM »
yea shorter axle and shorter housing all mean less weight and the reason I have spacers. Some call it greedy I call it getting all I can.
Relecting obama is like shooting right foot because it did not hurt enough when you shot left foot

Offline sawdawg

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Re: wheel backspacing
« Reply #7 on: November 19, 2018, 03:42:26 PM »
Does the one inch tire bulge seem like the right amount ?

Offline rooman

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Re: wheel backspacing
« Reply #8 on: November 20, 2018, 04:32:42 AM »
Does the one inch tire bulge seem like the right amount ?

That really depends on wheel vs tire width, tire size and construction etc but is usually pretty close.

Roo
Yeah, I am from the south--any further south and I would have been a bloody penguin.

Offline gregm784

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Re: wheel backspacing
« Reply #9 on: November 21, 2018, 11:08:00 AM »
I too like about 1/2" - 1".  Mine have only kissed a couple times (when it shakes super hard). 
« Last Edit: November 21, 2018, 11:10:17 AM by gregm784 »
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