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Can you run higher offset rear wheels on GT350R without rubbing inboard?

Champale

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Hey guys,

With an eye towards running GT500-spec tires (305/30/20, 315/30/20) on some Signature wheels, I am curious about whether or not GT500-spec rear wheels could be used on a 350R. I saw a GT500 CFTP at the local auto show and the rear wheels sit flush, unlike the pronounced poke on the 350Rs. I have been speaking with Terrance/50 Deep and I'm not sure we have a definitive answer. I don't have a 350R yet (on order, hopefully getting it in a few months) so can't take measurements or look for myself.

Any reason the rear wheels couldn't be made in a 20x11.5 ~ET61? That's 5mm further inboard than OE. And I guess if it did rub, I could always add a small spacer.

Thank you!

John
 

Champale

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Hey thank you for the reply, Rick. As of right now, Terrance can't quite guarantee that GT500 rear specs will fit without rubbing on a 350. If I had the car already, I could compress the suspension and check the clearances. I just can't imagine that they wouldn't work because, other than an E-brake difference between the cars, I haven't seen anything saying that the inner fender area is any different between the cars.
 

JAJ

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Hey thank you for the reply, Rick. As of right now, Terrance can't quite guarantee that GT500 rear specs will fit without rubbing on a 350. If I had the car already, I could compress the suspension and check the clearances. I just can't imagine that they wouldn't work because, other than an E-brake difference between the cars, I haven't seen anything saying that the inner fender area is any different between the cars.
The apparent lack of "poke" on the GT500 could be because of the difference in the rear alignment. The GT500 Owner's Supplement indicates a rear camber track setting of -2.2 degrees. The track setting for the GT350R is only -1.6 and the street setting is around -1.0.

If the photos we've all seen of GT500's are of cars set up at the track specs, then the top of the tire could be as much as an inch further inboard than a car set up for the street even if everything else was the same.
 

Champale

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Ah very interesting point! I am probably overthinking this because between using higher offset wheels plus possibly spacers and/or camber adjustments, I can probably get the handling setup I want PLUS wheels that don't poke.

But why the heck has no one pulled a wheel off their new GT500 to see the ET stamp?? Please people please!
 

byronj

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Ah very interesting point! I am probably overthinking this because between using higher offset wheels plus possibly spacers and/or camber adjustments, I can probably get the handling setup I want PLUS wheels that don't poke.

But why the heck has no one pulled a wheel off their new GT500 to see the ET stamp?? Please people please!

Because there are not that many GT500 owners out there and the ones that do have it are too busy driving their car. Think about how many new questions arose when the GT350 came out and how little data there was for the first few months.
 
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APEXRaceParts

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There is not a ton of inboard room with the 11.5" ET56 wheels out back, but from what we saw if you're sticking with a 315 width, you could go in 2-3mm and still have room. Now every tire is a little different so that comes into play, along with negative camber as mentioned above. If you wanted to run something wider like a 325 in the future, you could run into issues with a higher offset.

- Cory
 

Champale

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Hey Cory - thank you very much for that information! Have you had a chance to look at a new GT500 inner fender area? Just curious if there is any difference that you noticed.
 

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