Help me understand Backspacing vs Offset
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Is it basically an expression of the same thing?
I have a really nice set of Speedline Corse 2308's I want to use on my ws6, but i cant figure out if they'll work or not.
Will a 17x8.5 with 4 7/8" backspacing fit on the front?
How about a 17x10 with 6 1/4" backspacing on the rear?
These are originally for a BMW fitment. Basically the same bolt pattern as ours though.
Do you think I'd be able to use a 315 tire in the back okay?
I have a really nice set of Speedline Corse 2308's I want to use on my ws6, but i cant figure out if they'll work or not.
Will a 17x8.5 with 4 7/8" backspacing fit on the front?
How about a 17x10 with 6 1/4" backspacing on the rear?
These are originally for a BMW fitment. Basically the same bolt pattern as ours though.
Do you think I'd be able to use a 315 tire in the back okay?
![](http://www.thirdgen.org/techboard/attachments/auto-detailing-appearance/67753d1080423704-where-can-i-get-speedline-2308.jpg)
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I fit them on w/o tires and it looked really close. Tires tell a different story though. I don't want to have tires mounted to them and they not fit. Then I go from rims I can get my money back out of to $500 rims because they were "mounted".
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Offset and back spacing are related, but one cannot really be determined exactly by knowing one or the other . . . you can guesstimate . . .
Lets do the math on the 8.5" wide wheel. I am going to assume the rim beads are 1/2" thick making the wheel physically 9.5" tall over all width. (FYI rim size is measured from the inside surfaces of the rim beads).
9.5" - 4.875" BS = 4.625"
9.5" / 2 = 4.75"
Presumed offset: 4.75"-4.625" = .125" or 3.175 mm . . . and no that will not fit.
Lets do the math on the 8.5" wide wheel. I am going to assume the rim beads are 1/2" thick making the wheel physically 9.5" tall over all width. (FYI rim size is measured from the inside surfaces of the rim beads).
9.5" - 4.875" BS = 4.625"
9.5" / 2 = 4.75"
Presumed offset: 4.75"-4.625" = .125" or 3.175 mm . . . and no that will not fit.
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Thanks man. That's a bummer....these rims look sweet!
Know anyone with a bimmer or 3rd gen f-body looking for a set of wheels?
I know it fits those.
Know anyone with a bimmer or 3rd gen f-body looking for a set of wheels?
I know it fits those.