SS wheel question.

[betelgeuse]

My car came from the factory with 17x9.5" front wheels and 18x10.5" rear wheels.
If I run 18' wheels on all 4 corners does the width have to be 9.5" or can it be 10.5". Or can I even run 18" on all 4 corners?

This is the wording in the rule book;
"Cars delivered with wheels greater than 17 inches in diameter may use wheels that are 17 inches or
greater in diameter, provided they are not larger than the stock diameter and width."

Thanks in advance,
Greg

[Chrispy]

That's going to depend on whether 18" wheels were a factory option for your trim level.

[betelgeuse]

That's where the confusion lies. It comes with 17x9.5" front and 18x10.5" rear.

Greg

[Stynger]

I think the rule lets cars that comes stock with wheels over 17" (18", 19", 20" etc) to run a 17"wheel.

If your car came with 19" wheels you could run 17",18"or 19".

You can't go larger than your stock size, or stock width.

You could run 17x9.5 front and rear, or 17x10.5 rear, not 18" front.

[betelgeuse]

I think the rule lets cars that comes stock with wheels over 17" (18", 19", 20" etc) to run a 17"wheel.

If your car came with 19" wheels you could run 17",18"or 19".

You can't go larger than your stock size, or stock width.

You could run 17x9.5 front and rear, or 17x10.5 rear, not 18" front.

Thanks Les,

I'll just run the stock set up. Unless someone else has a different interpretation.

Maybe the wording should be changed or an example given. Many of the performance cars these days come with staggered wheels.

Greg

[naschmitz]

There are other sanctioning bodies that interpret "Any type wheel may be used provided wheel size (width and diameter) remain stock" to mean you can run Corvette rears on all four corners of a Corvette, especially since that setup works well on a C5. COM rules do not specifically mention staggered setups and these are "Stock Rims," so I don' see where it is mentioned in the COM rules that you can't run rears at all four corners.

[betelgeuse]

There are other sanctioning bodies that interpret "Any type wheel may be used provided wheel size (width and diameter) remain stock" to mean you can run Corvette rears on all four corners of a Corvette, especially since that setup works well on a C5. COM rules do not specifically mention staggered setups and these are "Stock Rims," so I don' see where it is mentioned in the COM rules that you can't run rears at all four corners.

That's what I was thinking. It would be hard to DQ someone the way the rule is written. It doesn't say anything about front/rear. It just says;
".....provided they are not larger than the stock diameter and width."
That being said I think the intent is stock diameter and width front and rear. It really should be reworded.

Greg

[paultg]

There are other sanctioning bodies that interpret "Any type wheel may be used provided wheel size (width and diameter) remain stock" to mean you can run Corvette rears on all four corners of a Corvette, especially since that setup works well on a C5. COM rules do not specifically mention staggered setups and these are "Stock Rims," so I don' see where it is mentioned in the COM rules that you can't run rears at all four corners.

That's what I was thinking. It would be hard to DQ someone the way the rule is written. It doesn't say anything about front/rear. It just says;
".....provided they are not larger than the stock diameter and width."
That being said I think the intent is stock diameter and width front and rear. It really should be reworded.

Greg

Yeah, I know the general thought is 'if it isn't mentioned in the rules it isn't allowed" but this is certainly a gray area. - Paul G.

[Bobc]

I was told that I could not run the Z06 wheels on my c5 coupe because it was not a z06. so why would the 18 x 10.5 be allowed on the front? z06 wheels are 1 inch wider than c5 coupe wheels but are the same stagered 17 front 18 rear diameters.
Bob

[betelgeuse]

I was told that I could not run the Z06 wheels on my c5 coupe because it was not a z06. so why would the 18 x 10.5 be allowed on the front? z06 wheels are 1 inch wider than c5 coupe wheels but are the same stagered 17 front 18 rear diameters.
Bob

You don't have a z06 so you can't run the z06 wheels. IMO the way the rule is written (at the moment. I submitted a rule change) you can run the 18x9.5 on all 4 corners. That's the largest wheel that came with your car. If the BoD changes the wording and you want to run a square set-up you'd have to run 17x8.5. The smaller of the 2 widths that came with your car.

Edit: To be on the safe side last year when I ran my M3 in SSA I ran the stock m3 wheels 17x7.5 front and 17x8.5 rear.
Greg

[DanDarcy]

IMO the way the rule is written it calls for stock wheel size. The Corvette would be 17" on the front and 18" on the rear. That is stock, the way the car came out of the factory. Putting an 18" wheel on the front ( a non stock location for a stock wheel) would not be stock as it did not come from the factory that way, therefore putting 18" all around would not be legal in SS class. Putting Z06- C5 wheels on a regular C5 would not be stock either as the Z06 wheels are wider than the regular C5 wheels.

[nateh]

I would share Dan's interpretation.

[betelgeuse]

I would share Dan's interpretation.

....and I would too if it was worded differently. It says nothing about front/rear. It just says;
"...Cars delivered with wheels greater than 17 inches in diameter may use wheels that are 17 inches or
greater in diameter, provided they are not larger than the stock diameter and width."
The Corvette is delivered with 18" wheels.

Not only that, I think cars with larger than 17" wheels have a distinct advantage. They can run any wheel diameter all the way down to 17" as long as it stays at the stock width or less. Less rotating and unsprung weight than stock.


Greg

[Bobc]

IMHO I share Dan's and Nates interpretation 17 front 18 rear is stock.....The coupe thing was mentioned to show if that is not ok then why would 18's on the front be ok? at least the z wheels were available in the same model year but not originally installed on this car....I won't have issues I have stock OEM wheels on all 4 corners.

[breakaway500]

"provided they are not larger than the stock diameter and width." I interpret this to mean the stock wheels that came on the car,regardless of their position. Therefore,if you removed the STOCK 17" front wheels and replaced them with taller/wider wheels,you would be in violation of the rule.