wheel question again
Thread Starter
Racer
Joined: Jun 2004
Posts: 350
Likes: 0
From: Pa
wheel question again
sorry, I know that we are tired of wheel questions but I found a set of HRE wheels that the rear are 11" wide and were removed from a corvette. I am tryng to describe to the seller how to measure the backspacing. But my question is....Don't most 11" wheels stick beyond the wheel lip and aren't they for GS/ZR1 or vehicles with flares?
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
There are two wheel measurements you need to be familiar with when dealing with Corvette wheel applications: Backspacing and Offset.
Backspacing is typically measured in inches and is the distance from the face of the wheel mounting flange to the inside edge of the wheel.
Offset is the distance between the centerline of the wheel and the wheel mounting flange
1988 and later 17x9.5 Vette wheels will have a 56mm offset and a 7.4" backspace. An actual 17x11 wheel from a ZR-1 will have a 36mm offset and a 7.4" backspace. The Grand Sport 11" wheel will have a 50mm offset and about an 8" backspace.
Because the ZR-1 body was about 1.5" wider on each side compared to a standard C4, the wider wheel and different offset/backspacing for that wheel allowed it to sit "correctly" in the wheel well.
The GS coupe had flares in the rear as that 11" wheel did stick slightly outboard of the top of the wheelwell so the flares were added. The GS convertible used a 9.5" wide wheel on all four corners.
Backspacing is typically measured in inches and is the distance from the face of the wheel mounting flange to the inside edge of the wheel.
Offset is the distance between the centerline of the wheel and the wheel mounting flange
1988 and later 17x9.5 Vette wheels will have a 56mm offset and a 7.4" backspace. An actual 17x11 wheel from a ZR-1 will have a 36mm offset and a 7.4" backspace. The Grand Sport 11" wheel will have a 50mm offset and about an 8" backspace.
Because the ZR-1 body was about 1.5" wider on each side compared to a standard C4, the wider wheel and different offset/backspacing for that wheel allowed it to sit "correctly" in the wheel well.
The GS coupe had flares in the rear as that 11" wheel did stick slightly outboard of the top of the wheelwell so the flares were added. The GS convertible used a 9.5" wide wheel on all four corners.
