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Offset Questions

Old May 14, 2012 | 07:00 PM
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Default Offset Questions

So I'm ordering a custom set of Forged wheels and I'm lost on "Offsets"

I read over the sticky and if anything it only confused me more than I already was.

I'm gonna order a set of 17X9.5 and 17X11 wheels. My car has a factory length rear end and is factory height (for now), I bought the car with 11inch wide ZR1's (I'm not sure if they were GM or replicas) so it's had the BFH mod on it and I don't want to roll the fender at all!

9.5" ..... +38 to +56 mm .... 255, 265, 275, 285

11.0" ... +45 to +56 mm .... 305, 315, 335
So whats the difference? I do want to run 315's on the back (DR's) and 275's on the front.
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Old May 14, 2012 | 08:22 PM
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The lower offset, the further out the wheel will sit. The higher the offset, the more it'll sit in the wheel wells. I'd do A 45mm on the rears and roll the fenders.
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Old May 14, 2012 | 08:52 PM
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Originally Posted by Donohue96M6Z28
The lower offset, the further out the wheel will sit. The higher the offset, the more it'll sit in the wheel wells. I'd do A 45mm on the rears and roll the fenders.
I'm not rolling the fenders
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Old May 14, 2012 | 09:02 PM
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Then get 50mm offset (same as your ZR1s)

38mm in front will look best
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Old May 15, 2012 | 08:53 AM
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So what will stick out farther? The 50's or the 56's
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Old May 15, 2012 | 09:16 AM
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50mm will stick out more - lower the offset, more it will stick out
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Old May 15, 2012 | 09:58 AM
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Originally Posted by Grn4fbody
So what will stick out farther? The 50's or the 56's
Did you read my post?
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Old May 15, 2012 | 11:26 AM
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Originally Posted by Donohue96M6Z28
Did you read my post?
Yes I did, I think I got it now. I think I'm gonna go with a 47 or 50
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Old May 15, 2012 | 03:35 PM
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http://www.tirerack.com/wheels/tech/...jsp?techid=101
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Old May 15, 2012 | 03:59 PM
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Is there a write up on how to find the offset you need without a wheel? I should of done this before I sold my old wheels off.
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Old May 15, 2012 | 08:22 PM
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Originally Posted by Grn4fbody
Is there a write up on how to find the offset you need without a wheel? I should of done this before I sold my old wheels off.
Dooood... you're making this waaaaay more difficult than it should be. There's like a bajillion threads on here with tons of pictures of different wheels, sizes and offsets. Simply browse through the pictures, pick something you think looks good, then send a PM to that person asking him what the specs are on his wheels.
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Old May 15, 2012 | 08:24 PM
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Oh yeah... I forgot to post this:

https://www.rsracing.com/tech-wheel.html#backspace
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Old May 15, 2012 | 08:32 PM
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Serious

Take half the width of the wheel you're looking at, minus 3.5. Convert the answer to mm and thats the offset you need

11" ZR1. Half is 5.5 minus 3.5 equals 2in. Converted to metric is just a hair over 50mm
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