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38mm offset on later C4

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Old Dec 17, 2008 | 02:46 PM
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Default 38mm offset on later C4

I have a 91 vert and am looking at a set of ZR-1 aftermarket wheels. 17" X 9.5" w/ 38mm offset. I know they are not correct for the later C4, but wondered if anyone has this set up, does it look okay?
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Old Dec 17, 2008 | 05:57 PM
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Originally Posted by old guy with vette
I have a 91 vert and am looking at a set of ZR-1 aftermarket wheels. 17" X 9.5" w/ 38mm offset. I know they are not correct for the later C4, but wondered if anyone has this set up, does it look okay?
Thanks
Those would work fine. I have 17x11" w 38mm on my rears. They protrude about 1".

I like the wheels hitting right a flush or a tiny, tiny bit out. Factory has them in about 3/4". Needs to come out IMO.

I'm betting 38mm 9.5" wheels would be PERFECT! I don't think you'd rub up front either (unless you slam it).

DO IT!
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Old Dec 17, 2008 | 07:39 PM
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The stock wheel offset for your 91 is 56mm. The difference between the 56 and 38mm offset is about 3/4" and the early offset wheel will stick out that 3/4" further when compared to the stock wheels.

There should not be any real issues with the early wheels in terms of tire clearance. Vert's sit slightly higher than coupes (assuming the same springs) and that will help with clearance in the front wheelwells when the wheels are at full lock to either side.
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Old Dec 17, 2008 | 08:42 PM
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Originally Posted by c4cruiser
The stock wheel offset for your 91 is 56mm. The difference between the 56 and 38mm offset is about 3/4" and the early offset wheel will stick out that 3/4" further when compared to the stock wheels.

There should not be any real issues with the early wheels in terms of tire clearance. Vert's sit slightly higher than coupes (assuming the same springs) and that will help with clearance in the front wheelwells when the wheels are at full lock to either side.


Again, mine protrude about 1". Subtract 1/2 of the difference in tire width 11 - 9.5" = .75". Yours will protrude about 1/4". You won't even notice that (visually).

Notice too, they are about 1/2" set inside now.
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Old Dec 18, 2008 | 11:04 AM
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Originally Posted by GREGGPENN
Those would work fine. I have 17x11" w 38mm on my rears. They protrude about 1".

I like the wheels hitting right a flush or a tiny, tiny bit out. Factory has them in about 3/4". Needs to come out IMO.

I'm betting 38mm 9.5" wheels would be PERFECT! I don't think you'd rub up front either (unless you slam it).

DO IT!
Thanks Greg, I was concerned they wouldn't. I appreciate your help
Roger
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Old Dec 18, 2008 | 11:04 AM
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Originally Posted by c4cruiser
The stock wheel offset for your 91 is 56mm. The difference between the 56 and 38mm offset is about 3/4" and the early offset wheel will stick out that 3/4" further when compared to the stock wheels.

There should not be any real issues with the early wheels in terms of tire clearance. Vert's sit slightly higher than coupes (assuming the same springs) and that will help with clearance in the front wheelwells when the wheels are at full lock to either side.
Thanks for the feedback!
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