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OFFICIAL: wheel/tire picture thread... show em off!

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I decided to pull my wheels off and measure the backspacing and do this proper.

The photos are with ATR performance front springs and Moog cargo coils in the rear, both stock height that have sagged about an inch since their installation in 1988.
The suspension in the photos is stock other than the springs, huge sway bars, Bilstein shocks, KB lift bars (lower control arms, rear) and rear disc brakes by SSBC (rotor hats 1/8" thicker than drums)

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Wheels: HRE 504

Front: 17x8.5 4 5/8" backspace
Tires: 255/40ZR17

Rear: 17x9 4 5/8" backspace
Tires: 285/40ZR17

The front left tire contacted the rear of the A-arm during a full left lock counter steer on the auto X. I have since tweaked the A-arm.

The rear tires kiss the frame from time to time at the rear part that curves outward just behind the tire as the axle shifts and the tires flex through the slalom.

If I had the knowledge back in 1992 when I had these wheels made I would have went 9 wide in front and 9.5 wide in the rear to pull the tires out for more clearance.

And on a side note: Spoolfool rocks... :p
 
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I decided to pull my wheels off and measure the backspacing and do this proper.

Rear: 17x9 4 5/8" backspace
Tires: 285/40ZR17
That was a great job of wheel & tire upsizing...those rear tires are only about 3 mm shorter than stock tire diameter...probably doesn't even affect the speedometer calibration. It would seem a 4.5" backspace is an all-around safe bet for a maximum backspace to avoid frame rubbing.
 
That was a great job of wheel & tire upsizing...those rear tires are only about 3 mm shorter than stock tire diameter...probably doesn't even affect the speedometer calibration. It would seem a 4.5" backspace is an all-around safe bet for a maximum backspace to avoid frame rubbing.

Thank you. I measured so they (wheels) were close to the frame front and rear because rolling fenders wasn't a thing, and I didn't think of it.
I also didn't take into account that the tires would flex quite that much, or axle shift.
I went 4 5/8" backspace in the rear to account for the extra thickness of the disc brake conversion. Hopefully the UMI upper control arms with poly bushings will do a better job of keeping the rear axle located.

I had '86 Vette wheels (16x8.5) and 255/50ZR16 tires w/ 1.5" wheel adapters/ spacers on it prior, and that is what I measured from.
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Thank you. I measured so they (wheels) were close to the frame front and rear because rolling fenders wasn't a thing, and I didn't think of it.
I also didn't take into account that the tires would flex quite that much, or axle shift.
I went 4 5/8" backspace in the rear to account for the extra thickness of the disc brake conversion. Hopefully the UMI upper control arms with poly bushings will do a better job of keeping the rear axle located.

I had '86 Vette wheels (16x8.5) and 255/50ZR16 tires w/ 1.5" wheel adapters/ spacers on it prior, and that is what I measured from.
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I have to say, it took awhile for this combo to grow on me but I really like it now. They look right at home on that car.
 
I have to say, it took awhile for this combo to grow on me but I really like it now. They look right at home on that car.

I have always been partial to the flush look more so than the deep dish look.
That's why I went that route, but then couldn't resist the GNX look.
 
Just put these on today, had the rims widened to 9", I know, they make the aluminum one's in 8" or 10", 8'' isn't wide enough, and 10" is to wide. These rims have a 4.5" back space and the tire size is P255-60R-15 .
 

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(y)As soon as he tells us there will be a couple hundred sets rolling their way.
 
Just put these on today, had the rims widened to 9", I know, they make the aluminum one's in 8" or 10", 8'' isn't wide enough, and 10" is to wide. These rims have a 4.5" back space and the tire size is P255-60R-15 .
I think 9" should be a standard. Looks like GM should've done it in the beginning.
 
Have any more shots of the car with the new wheels on it? Looks awesome
I think I may have to hit Mario up once tax season comes!
 
Does anyone by any chance know what wheels are on this gnx?? Any info will be great! Or even wheels that are very similar. Thanks!
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Who makes the long braces under the hood of that GNX? I like that.
That's called electrical conduit (EMT). You can get them at Home Depot and then it does absolutely nothing but get in your way when you have to service your engine compartment.

Don't forget the spray paint.
 
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