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Will these fit???

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Old Nov 5, 2007 | 04:00 PM
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Default Will these fit???

I've been reading threads about wheels, backspacing, etc... and I still am not sure I fully understand how to tell what will and won't work. So, can anyone answer this, and how do you know (so, I don't have to ask again if I ever change wheels)?

Will these wheels fit???

Front = 18X8 w/ 38mm offset
Rear = 18X9 w/ 38mm offset

I have a 77 without flares and stock rotors/calipers/TA
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Old Nov 5, 2007 | 05:05 PM
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38mm offset? Maybe I'm just not thinking correctly. What's the back spacing?
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Old Nov 5, 2007 | 05:29 PM
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38 mm = 1 1/2 inches offset Not sure about a 1977, but rim offset shoud be around 4 3/4 inches. I'm sure someone will help if I'm wrong.
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Old Nov 5, 2007 | 05:32 PM
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Originally Posted by Glass Act
38 mm = 1 1/2 inches offset Not sure about a 1977, but rim offset shoud be around 4 3/4 inches. I'm sure someone will help if I'm wrong.

Stock C3 back spacing was I think 4". More is better. I was confused by offset. Maybe he means outside dish depth?
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Old Nov 5, 2007 | 05:34 PM
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Originally Posted by Durango_boy
38mm offset? Maybe I'm just not thinking correctly. What's the back spacing?
I think it would be:

5.5" Front
6.0" Rear

It's the center line + the offset correct???
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Old Nov 5, 2007 | 05:54 PM
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Originally Posted by JP_80
I've been reading threads about wheels, backspacing, etc... and I still am not sure I fully understand how to tell what will and won't work. So, can anyone answer this, and how do you know (so, I don't have to ask again if I ever change wheels)?

Will these wheels fit???

Front = 18X8 w/ 38mm offset
Rear = 18X9 w/ 38mm offset

I have a 77 without flares and stock rotors/calipers/TA
In a word, no.

They are positive offset wheels, so that means the mounting flange is outboard of the centerline of the wheel. Stock 'vette is approximately -11mm offset on an 8" wide wheel.
38mm offset on an 8" rim, would be about 6" of backspace.

Nick
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Old Nov 5, 2007 | 06:29 PM
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Originally Posted by lvrpool32
In a word, no.

They are positive offset wheels, so that means the mounting flange is outboard of the centerline of the wheel. Stock 'vette is approximately -11mm offset on an 8" wide wheel.
38mm offset on an 8" rim, would be about 6" of backspace.

Nick

Thanks for the info Nick.

What is the max backspacing you can have with stock setup?
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Old Nov 5, 2007 | 08:22 PM
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Will a +20mm on a 18X8.5 wheel work?
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Old Nov 5, 2007 | 08:45 PM
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that would give you a 5.5" backspace wheel.

You could make these wheels fit by using a 1.5" wheel adaptor (thats a spacer that bolts to your existing hub, then you bolt your wheel to the spacer)
A lot of guys here do that so they can use C4/C5 wheels.

Nick
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Old Nov 5, 2007 | 10:23 PM
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backspace is the measurement from the wheel lip to the mounting flange the offset is the measurment from center +or-
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Old Nov 6, 2007 | 04:43 PM
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Originally Posted by lvrpool32
that would give you a 5.5" backspace wheel.

You could make these wheels fit by using a 1.5" wheel adaptor (thats a spacer that bolts to your existing hub, then you bolt your wheel to the spacer)
A lot of guys here do that so they can use C4/C5 wheels.

Nick
Does that mean I could get the 38mm offset wheels to fit if I used a 2" adaptor? These wheels are listed to fit a C4 vette.
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Old Nov 6, 2007 | 05:11 PM
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yup
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Old Nov 6, 2007 | 06:03 PM
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Originally Posted by lvrpool32
yup
Thanks!
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