Wheel Whore advice needed

JEWC_Motorsports

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Im looking at running a 17x11 with a 295 45 in the rear. Will it fit? What backspacing will i need? 17x10 is 7.5" backspace so is a 17x11 8.5" backspace? Help me out please as i couldnt find anyone running this size.
 
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joedls

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Im looking at running a 17x11 with a 295 45 in the rear. Will it fit? What backspacing will i need? 17x10 is 7.5 so is a 17x11 8.5? Help me out please as i couldnt find anyone running this size.

What do you mean when you ask if it's 8.5? Is what 8.5?
 

csamsh

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Check the sticky:

Common Offsets
9" +24 to +45
9.5" +30 to +45
10" +36 to +51
10.5" +42 to +57
11" +59 or greater
 

csamsh

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Offset doesnt help me.

it does-

backspacing and width are in inches, offset is in mm

Backspacing=(width/2)+(offset/25.4)

backspacing measures hub to inner lip of wheel, offset measures hub to centerline of wheel
 
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Mystickeith50

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James there was a guy on here that had a red coyote and competed in kots....I believe he had 17x11s in the rear...Forgestars. Damn I can't remember his screen name.
 

JEWC_Motorsports

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The only size i can get is 17x9.5 which i dont want, 17x11 or 15x10. Id prefer to have 17's all around.
 

Mystickeith50

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James try calling forgestar. I know the guy on here had 17x11s. Maybe you remember him. He had a red coyote with a pro charger in kots. Sold it and got a 13 gt500. Forgestar will at least tell you the offset for that wheels size.
 

Norm Peterson

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it does-

backspacing, width, and flange thickness are in inches, offset is in mm

Backspacing=(Width/2)+Flange Thickness+(Offset/25.4)

backspacing measures hub to inner lip of wheel, offset measures hub to centerline of wheel
Fixed.

You need to the flange thickness in your above formula, because "advertised" wheel width (the only width number you'll ever see) is measured between the bead seats (inside the flanges) while backspacing measures to the overall back side of the wheel which has to include the inner flange. Offset works directly with bead seat width and ignores the flanges entirely. One flange thickness is approximately half an inch, though some wheels can run a little wider. It is usually safe to assume that the inner and outer flanges are the same thickness although I know of no requirement that they be the same.


I also question the wisdom of considering 17 x 11's when tire availability is better in 18 and 18 x 11's that can fit the tire treads under the sheetmetal are readily available. And I think that 18 is past bordering on being large.


Norm
 
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cbass

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Fixed.

You need to the flange thickness in your above formula, because "advertised" wheel width (the only width number you'll ever see) is measured between the bead seats (inside the flanges) while backspacing measures to the overall back side of the wheel which has to include the inner flange. Offset works directly with bead seat width and ignores the flanges entirely. One flange thickness is approximately half an inch, though some wheels can run a little wider. It is usually safe to assume that the inner and outer flanges are the same thickness although I know of no requirement that they be the same.


I also question the wisdom of considering 17 x 11's when tire availability is better in 18 and 18 x 11's that can fit the tire treads under the sheetmetal are readily available. And I think that 18 is past bordering on being large.


Norm

Fixed. Offset is determined by the center line of the wheel, so a wheel that is 8" wide with an offset of +44 will require one inch less backspacing than a wheel that is 10" wide with that same +44
 

csamsh

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I think what we really need to say is "it depends on the manufacturer..." do they differentiate between wheel and rim width? Where do the measure from? Are the flanges differently shaped? I don't think any one "formula" can work with any wheel.
 

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