Max Wheel size clarification

R

rpiekarczyk

New member
Hello all...

Trying to remeber, but my memory isn't serving any justice and I can't seem to find it in Fastrack. There was some discussion of creating a "Max Wheel Size" on each car's spec line... I seem to remember that going into effect 1/1/12... but can someone confirm this for me? THerefore, if the Max Wheel size was 17x7, I could then run a 15x7 if I wanted.

Thanks!
Rob Piekarczyk
 
According to the current letter of the GCR (page 395 is where the relevant stuff is.) http://www.scca.com:8080/assets/GCR-UpdatedThroughNovFastrack.pdf

Your spec line calls for 17" wheels, therefore you MUST run a 17" diameter wheel:
9.1.3.7.a.1 said:
...Cars may not fit wheel diameters smaller than those listed on their spec line...
Click to expand...

But you can run a Max width of 7". i.e. you can run a 5 or 6" width if you want, but why would you want to do that? ;)
9.1.3.7.a.6 said:
Maximum allowable rim widths: ITR - 8.5 inches, classes ITS and ITA - seven (7) inches; classes ITB and ITC - six
(6) inches.
Click to expand...

However, I remember hearing somewhere that it was supposed to be changed to a MAX wheel diameter, not a spec-line diameter. It's not stated in the GCR, so it ain't true tho- at least for today. I would think that if it were going to be allowed in 2012, it would already be listed in the GCR in redline form and said not to go into effect until Jan 1, 2012.
maybe it was listed in Fastrack as a "tell us what you think" instead of an actual rule change?

Of course I could be completely wrong and just unable to find it (and I'm not going to spend two hours reading through all of this year's Fastrack updates to find it..)
 
My head is mush after reading through everything... I found this in the June Fastrack. It is under the "suggested rules" for next year being sent to the BOD. Otherwise, I can't find anything... but I could have sworn I read somewhere that it was approved... I could be wrong though.

Back to searching...

(Multiple) Support for modification of wheel diameter rules
The CRB thanks all those who responded to the request for input on IT wheel diameter rules, resulting in the following rule proposal.
In 9.1.3.D.7.a.1 change as follows:
[FONT=Arial,Arial][FONT=Arial,Arial]Cars originally equipped with twelve (12) inch wheels may fit thirteen (13) inch wheels. Cars originally equipped with metric 365 wheels may fit fourteen (14) inch wheels, and cars originally equipped with metric 390 wheels may fit fifteen (15) inch [/FONT][/FONT]wheels. The above-mentioned cars as well as those cars originally equipped with thirteen (13) inch or fourteen (14) inch [FONT=Arial,Arial][FONT=Arial,Arial]wheels may fit up to a fifteen (15) inch wheel. Cars may not fit wheel diameters [/FONT][/FONT]smaller [FONT=Arial,Arial][FONT=Arial,Arial]larger [/FONT][/FONT]than those listed on their spec line. All other cars shall [FONT=Arial,Arial][FONT=Arial,Arial]retain the wheel diameter fitted as original equipment for their make, model, and type. [/FONT][/FONT]Knockoff/ quickchange type wheels are prohibited. Wheels must be made of metal. [FONT=Arial,Arial][FONT=Arial,Arial]Cars classified in ITR may utilize any wheel [/FONT][/FONT]diameter up to 17" or retain their stock diameter wheels if larger.
All ITS/ITA/ITB/ITC cars currently listed in the ITCS with a wheel size less than 15 inches would be changed to 15 inches. All ITR cars currently listed in the ITCS with a wheel size less than 17 inches would be changed to 17 inches.
The heading on the wheel size column would be changed to "Max Wheel Diameter".
 
SCCA has implemented a policy of "rules year", which means that rule CHANGES will not happen in the middle of the year ("change" does not include classification and competition adjustments, such as weight and restrictors.) Thus, since this is truly a CHANGE it will not have been approved prior to the next racing year, 2012.

That rule is still waiting for BoD approval. It probably will be approved, but I'd not go spend money just yet.
 
Interesting that ITR has always been allowed any size up to 17"... Either way I assume the new rule passed already for the other IT classes :)

Stephen

Existing rule: "Cars classified in ITR may utilize any wheel diameter up to 17" or retain their stock diameter wheels if larger."
 
StephenB said:
Interesting that ITR has always been allowed any size up to 17"... Either way I assume the new rule passed already for the other IT classes :)

Stephen

Existing rule: "Cars classified in ITR may utilize any wheel diameter up to 17" or retain their stock diameter wheels if larger."
Click to expand...

..And cars in IT S-C can go "up to 15in" in the same manner. the new rule would allow you to go backwards. so say an ITC new beetle (16" wheels stock, 6" wide max for the class) can go pick up some readily available 14x6" wheels rather than custom ordering or using some OEM 16x6 "saw blades" and finding tires to match.
 
Who is on the board?
The board is doing a terrible job if the wheel size rule dictates a change from stock size, to be complient.
Simply use the ITR wording.
 
Chip42 said:
..And cars in IT S-C can go "up to 15in" in the same manner. the new rule would allow you to go backwards. so say an ITC new beetle (16" wheels stock, 6" wide max for the class) can go pick up some readily available 14x6" wheels rather than custom ordering or using some OEM 16x6 "saw blades" and finding tires to match.
Click to expand...

I read the ITR rule to say if I wanted to use 14x6 on my ITR car I already could since I can use anything "up to" 17 (actually 18" on my car).
 
Mike O - log onto your member login at scca.com (green button, right side of the header). open the directory, under resources, and you can see any advisory comittee, the CRB, and the BoD members' names, addresses, phone numbers...

but the wheel width thing is a 100% firm limit. it establishes a rough traction limit for each class, allowing OEM wheels larger than the class limit would potentially unbalance the cars in that class. So if stock wheels are wider than allowed by the class the car falls into (6 B,C/7 A,S/8.5 R), that's too bad. most likely you will be replacing your stock wheels anyhow. the new rules will allow you to do so with anything up to the stock diameter or 15" (whichever is greater) and up to the class allowed width. excuses are pretty well nil at that point. you can almost always get a wheel that fits off the shelf, even if it's not what you "want". if you can't find a wheel to fit your car and the class allowances, then it falls under "warts and all" and you'll have to go custom.

ITR currently has similar rules with a "cap" at 17" diameter or stock and 8.5" width.
 
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