October 2025 Fastrack Preliminary Minutes/Tech Bulletin
09/18/25 - Preliminary Minutes
09/18//25 - Preliminary Tech Bulletin
09/18/25 - Preliminary Minutes
09/18//25 - Preliminary Tech Bulletin
October 2025 Fastrack
- Thread starter Greg Amy
- Start date
Well here's my chance to win the Runoffs. Come in 23rd and protest everyone on front of me based on a poorly worded wheel dimension rule.
Strikes me that as worded somewhere between "all" and "half of all" wheels that are nominally at the max size for the class would be in violation of this, depending on interpretation, roundness, and production tolerances. I interpret "absolute maximum" to mean that 0.001" oversize is illegal.
Ironic that the next item adds a tolerance to throttle body ID.
Strikes me that as worded somewhere between "all" and "half of all" wheels that are nominally at the max size for the class would be in violation of this, depending on interpretation, roundness, and production tolerances. I interpret "absolute maximum" to mean that 0.001" oversize is illegal.
Ironic that the next item adds a tolerance to throttle body ID.
A little bit of language evolution regarding wheel regulations, is this perhaps some foreshadowing and structuring for a forthcoming wheel update? 2 years and going on that letter...
"Rim width and diameter are
This is an edit to GCR Appendix G, so not affecting Prod specifically. And since it was done mid-year it's clearly an "errors and omissions" to clarify intent, not a regs change (which requires BoD approval).
And do note that listed diameters were already "max" allowances; see column labels in the spec sheets.
If you're worried about adding these as diameter tolerances (which cannot be measured to .001") then why were you not worried about it when width was already in there as an absolute? Wouldn't it be a lot more useful to exceed width, and a lot harder to measure (because of the tapered walls)? Are you implying that competitors have been fabricating wheels that are larger than the allowed diameter (which must be one hell of a fun thing to deal with when installing standard-sized tires) and they'll now get dinged for exceeding that? I find that hard to believe, honestly.
I can't offer why the PAC proposed this (other than to remove the word "max" in the spec lines column label) but I see concern over this as "a tempest in a teapot". - GA
The only reason that I even thought about it (with respect to width OR diameter) was the change. But when I DID think about it, I remembered Prod cars (at least one anyway) being DSQ'd for a valve 0.001" over the maximum dimension.
No, I have no thoughts that anyone is specially making marginally oversized wheels, especially wrt diameter, which as you say would only serve to make tires harder or impossible to mount. Nor do I really think that anyone is really making 7.1" wide wheels as a cheat, though it might be tempting..
It just seems a bit unwise to use the term "absolute maximum" on something that is extremely difficult to actually measure and subject to largely unknown tolerances. I was perhaps inspired by the wisdom of an Internet sage who once said something to the effect of "If a rule can't be enforced it isn't a rule".
In this case I'd modify it to "If a rule shouldn't be enforced as written it should be written differently".
I'm really not in the least personally concerned, and probably being a bit pedantic, but I do think that using the words "absolute maximum" on something that is in many ways a nominal dimension (unless you are armed with an SAE or ISO standard) is maybe setting a landmine in the rulebook that may or may not ever get stepped on.
Anyone wondering what I'm on about - go measure a road wheel and tell me EXACTLY - down to the thousandth - the diameter and width. No cheating by looking at the cast in nominal dimensions.
No, I have no thoughts that anyone is specially making marginally oversized wheels, especially wrt diameter, which as you say would only serve to make tires harder or impossible to mount. Nor do I really think that anyone is really making 7.1" wide wheels as a cheat, though it might be tempting..
It just seems a bit unwise to use the term "absolute maximum" on something that is extremely difficult to actually measure and subject to largely unknown tolerances. I was perhaps inspired by the wisdom of an Internet sage who once said something to the effect of "If a rule can't be enforced it isn't a rule".
In this case I'd modify it to "If a rule shouldn't be enforced as written it should be written differently".
I'm really not in the least personally concerned, and probably being a bit pedantic, but I do think that using the words "absolute maximum" on something that is in many ways a nominal dimension (unless you are armed with an SAE or ISO standard) is maybe setting a landmine in the rulebook that may or may not ever get stepped on.
Anyone wondering what I'm on about - go measure a road wheel and tell me EXACTLY - down to the thousandth - the diameter and width. No cheating by looking at the cast in nominal dimensions.
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I was perhaps inspired by the wisdom of an Internet sage who once said something to the effect of "If a rule can't be enforced it isn't a rule".
Sure, I get it. But I do think, in that context, that concern about wheel diameter as an absolute max tolerance is less worrisome than wheel width...which was already in there. We didn't complain about it, though...
Curious why the PAC pursued that. There's gotta be a back story.