wheel fitment
Thread Starter
Intermediate
Joined: Jan 2013
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wheel fitment
I have a 1987 corvette with z-51 suspension and it is lowered. I need a set of new wheels and I have measured the wheels that are currently on it and it appears they are a 17x9.5x 5.120 with a 56mm offset and they are fine, no rubbing just a perfect fit but I see the car is supposed to have a 38mm offset. Is this possible that they are really 56mm offset rims or am I measuring wrong? Thank You
Melting Slicks
Joined: Mar 2001
Posts: 2,149
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From: Timra, Sweden
http://www.joby.se/corvette/div/corvette_wheels/
The 56mm offset rims probably fit just fine without rubbing. The 11" wide ZR1 rims with the same 7.4" backspacing as your rims fit the early C4 corvettes.
To sit 'right' your rims should be 18mm further out.
The 56mm offset rims probably fit just fine without rubbing. The 11" wide ZR1 rims with the same 7.4" backspacing as your rims fit the early C4 corvettes.
To sit 'right' your rims should be 18mm further out.
Last edited by JoBy; May 11, 2017 at 02:45 PM.
Thread Starter
Intermediate
Joined: Jan 2013
Posts: 45
Likes: 0
http://www.joby.se/corvette/div/corvette_wheels/
The 56mm offset rims probably fit just fine without rubbing. The 11" wide ZR1 rims with the same 7.4" backspacing as your rims fit the early C4 corvettes.
To sit 'right' your rims should be 18mm further out.
The 56mm offset rims probably fit just fine without rubbing. The 11" wide ZR1 rims with the same 7.4" backspacing as your rims fit the early C4 corvettes.
To sit 'right' your rims should be 18mm further out.
Team Owner
Joined: Sep 2003
Posts: 25,385
Likes: 2,737
OP - generally speaking the wheel width & offset will be cast into the wheel back-side - it would be unusual that it wouldn't be. You really need to be sure! Unless you know the actual width of the wheel you can't use "back-spacing" measurements to convert to offset.
If you're buying new wheel/tire combinations you want to work with very specific dimensions and specifications.
Check and measure again!!
If you're buying new wheel/tire combinations you want to work with very specific dimensions and specifications.
Check and measure again!!
Safety Car
Joined: Aug 2013
Posts: 4,427
Likes: 604
From: Minneapolis Mn
Correct me if I'm wrong, but didn't the 87's come with 16" wheels also? If I'm correct I would expect they came like my 86. They had 2 sizes of rims, 16x8.5 +32 or 16x9.5 +38mm backspacing.
I know a number of people have used later rims on the early C4's. Apparently most have had to use spacers to make the rims fit properly when using +56mm backspace rims.
I changed the rim diameter on my 86 recently going from 16" to 18". I was fortunate in that I found some 18x9.5 +40mm backspace rims and they fit like the originals. Used 18x40zr18 tires and they fit just like the oem's would have except a larger rim diameter, giving a wider selection of tire options.
Here's a web page that may give some help making decisions: https://www.wheel-size.com/calc/?whe...cl=50mm&sr=0mm
You can put in what you have and what you want and see how they compare.
I know a number of people have used later rims on the early C4's. Apparently most have had to use spacers to make the rims fit properly when using +56mm backspace rims.
I changed the rim diameter on my 86 recently going from 16" to 18". I was fortunate in that I found some 18x9.5 +40mm backspace rims and they fit like the originals. Used 18x40zr18 tires and they fit just like the oem's would have except a larger rim diameter, giving a wider selection of tire options.
Here's a web page that may give some help making decisions: https://www.wheel-size.com/calc/?whe...cl=50mm&sr=0mm
You can put in what you have and what you want and see how they compare.
Last edited by hcbph; May 12, 2017 at 06:05 AM.
