Wheel width, ITB, again

What are your thoughts in wheel widths in ITB and ITC?


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2. I believe when the issue of ITA cars being reclassified came up about 2 years ago, there was mention that there was no competitive advantage of 7" over 6" rims. If that be the case, then to allow 7" in ITB would not affect the status of any other driver/car because it would not put the pressure on to go out and buy another set of whels.

I would suggest a test, using the same tires and same car/driver to verify no advantage is observed. I run SM Hoosiers, they fit both 6" and 7" rims. The Club does tire tests every year I think. We could run this test with both FWD and RWD cars to gain some data and review the results. Of course pressures would have to be adjusted with trial runs to gain the set data for the 2 different sizes.

I would definitely support this... as mentioned, found myself in the same boat - and we too are running the same size tire on 6's as we did on 7's. Don't know if it made the car slower or faster; I got a whole lot faster as a driver in the meantime, with basically no changes to the car, so can't say for myself.

Hmmm... for that matter, we do happen to have 7" rims around probably still too...

Then we'd need someone to either swap rubber back and forth on rims, or get two identical sets of new tires to mount up and compare.

I'd be willing to volunteer my services (car and driver) at a reasonably local track that I know well enough (Waterford would be an EASY way to line this up, cheap, on a practice day - $20 per session!), etc, to pursue this - at least provide the data for a RWD car. But I can't afford to buy two new sets of rubbers - not in my budget, I'm not even really running this year... :( Mid-O would be my other choice, but it is more expensive to get there and run...

EDIT - added bonus, I DO have a full-blown data system to provide quite accurate detailed results too...
 
It's not that simple to just test on one track. Some tracks will work better with a 205 vs 225, others the opposite. Same general thing with the overall contact patch provided using a 225 on a 6" vs 7" rim. For handling tracks, I'd sure take the 7" rim. I know a while back Tom Fowler from OMP Motorsports had done some testing at Road Atlanta using different tire widths. His conclusion was that the wider tire (225s) provided the best results.

Do you think there would be a difference between a 5" and 6" rim? What about a 4" and 6" rim? I'm sure the graph wouldn't be linear, but there have to be points on it where the gains and losses hit more. Even for the sake of perception, ITB drivers will feel the need to purchase the wider rims. It sucks for existing racers in ITB. I too came from ITA and understand that this wheel change makes it more complicated than just swapping out an A for a B using vinyl.
 
i do sort of agree with Vaughn that some of the comments are muddying the waters. but some of my comments were geared towards what do we do for newer cars?

for newer entrants that are not stuck in the 80's for a chassis like some of us, i think there must be newer cars (e.g., that have done their 5 year required stint in showroom stock) that had rims wider than 6" that should be considered.

since there are several versions of the dodge charger/shelby in ITB, it would be simpler if the VIN rule could let him use the 4 bolt hubs from the "sister" cars.

and one other thing that might get us further into this is the fact that Chrysler Dodge as we recently knew it is going away. flexibility of parts might become more pressing because of the bankruptcy.

hope this does not come across as argumentative but just trying to toss out ideas since some of what was the "norm" will be changing.

tom

p.s. i will get my note out about AWD and turbos (e.g., i see one liter turbos in ITB's future) in the next day or so as well. i might toss in a comment about allowing OEM wheel widths in IT.
 
p.s. i will get my note out about AWD and turbos (e.g., i see one liter turbos in ITB's future) in the next day or so as well. i might toss in a comment about allowing OEM wheel widths in IT.

What I would like to see regarding OEM parts is a blanket statement early in the ITCS that states that STANDARD EQUIPMENT from a listed car may be used, but any aftermarket parts, optional factory equipment, or dealer-installed equipment must adhere to the specifications in the main body of the ITCS.
 
I'd respectfully suggest that it's not possible to "prove" that the 7" wheels don't provide an advantage over 6" wheels. And even if repeatable tests demonstrated that it was the case, the results won't generalize to accommodate all of the other potential variables (e.g., fender width, cars with relatively high race weights).

I'll ignore the question of PERCEPTIONS of competitive advantage. That's another ball of worms.

There just aren't any "good" answers. They all seem "obvious" but only if viewed from one perspective or another. The clearest answer I've heard on the subject is that allowing 7" wheels is a money-saving answer if and only if that's all you've got. Otherwise it's a money spender.

K
 
1. When I threw this question out, I was wanting to get some feedback one the idea of considering changes to the rules based on the marketplace and availablility of parts. We have allowed changes base on parts and system developments before. Take the open ECU issue. It has far more serious implications on IT than the question of 7 " rims in ITB. Yet, because there are many drivers running FI, it passed the muster really quite easily. I must have been because the marketplace made somthing available that made working on your OEM ECU outdated or harder or more expensive.

2. I believe when the issue of ITA cars being reclassified came up about 2 years ago, there was mention that there was no competitive advantage of 7" over 6" rims. If that be the case, then to allow 7" in ITB would not affect the status of any other driver/car because it would not put the pressure on to go out and buy another set of whels.

I would suggest a test, using the same tires and same car/driver to verify no advantage is observed. I run SM Hoosiers, they fit both 6" and 7" rims. The Club does tire tests every year I think. We could run this test with both FWD and RWD cars to gain some data and review the results. Of course pressures would have to be adjusted with trial runs to gain the set data for the 2 different sizes.

This, cosidering all the responses to my original inquiry might be the best way to see through everyone's opinion and gain real data on which to base our rule making process.

The ECU issue is a totally different deal. What we have there is making the best of a bad situation created with a badly written/drafted rule. There were two rule steps to get here. Not relevant to this situation at all.

I certainly would not view the results of one test at one track with one driver as evidence either way on this issue.

I don't have any problem going to 7" wheels. I'll start shopping for some tomorrow if that is where we end up - because I do believe they represent a performance improvement, and my tire guy will like not stuffing 225/45 tires on my 6" wheels. HOWEVER. The argument that they are not available at reasonable prices does not hold water to me, especially in 5x100 bolt patterns.

All the VR6 VWs use that bolt pattern, and the first generation of them had 15" wheels.
All the 98-04/5 8 valve VWs came with 15x6 alloys.
You can buy custom configured 15x6 wheels from Compomotive if you like. In 18#, 17.2#, and others with unlisted weight.
Spin Werks will make custom wheels as well. They are in the $200/ea range last I checked on 13x6 sizes for 9# wheels, I imagine they can field a competitive 15" weight also.

The real question that needs to be discussed is justification beyond that it is harder for you to get what you want for a deal. Not all that long ago, I would never have expected the allowance for 15" wheels on any car that had smaller wheels stock, but we have that now. (of course as noted in the other thread, we now have some cars int eh 6" wide classes with larger oem sizes and no stock 16" options that are narrow enough. Now those guys may have more argument - 16x6 - 5x100....).

Greg pointed out that a common response is that folks have already invested in 6" wide rolling stock, and how that is a natural selfish reaction. Well I guess my response is selfish in that I don't want to make a change that may penlaize some, or many, or all of my current compeititors for the benefit of very few.

I would love to get 7" wheels, because I could then share wheel inventory with my prod car racing friends, but I'm not convinced there is a valid argument yet. I'm also not awfully steadfast in that position. I am close enough to the middle to be swayed.
 
OK, I'm gonna skip all the replies here and go back to address the orig post - 'cause I think there's a bit of wandering induced.

Inevitably when ITB wheel width comes up, it's a discussion of supply. Yet, at the same time, it tends to be a statement of "this will save me money/give better/faster options" rather than "I can't find ANYTHING that will fit, at any reasonable cost."

On that basis right there - it seems that this proposal will not be consistent with IT philosophy, no?

Questionable. We allow a large number of modifications that do not strictly fall in the category of "modifications to those useful and necessary to build a safe race car."

Seems to me you yourself have stated that you do have options - heavy stock rims, or expensive aftermarket rims - they're just not attractive to you.

And this is where we get into the old "you made that choice when you built the car."

I too have a former ITA car that moved to ITB; we too had to pitch a bunch of 7" readily-available old factory rims (from 944s) to use only 924-specific, harder-to-find rims.

That's the bed we've all individually made, and now we can lie in it... or move to a different car. Personally, I'm happy to stay in B, skinny wheels and all!!!

Which somewhat runs contrary to the old "you made that choice when you built the car." People built the car to run in a different class and purchased wheels based on that classification. The Club, changed the rules on them.

For these tweener cars that saw their wheels outlawed, I see no harm in duel classification (run the old class and be uncompetitive, but save on wheels). Nor do I see rules creep/special treatment in allowing these cars to run the wheels they ran in their old class - provided they are not dual classified.
 
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Historically, the ITAC gets requests like this regularly, and it always seems that there are options. But the writer of the request rejects them for some reason, or isn't aware of them.

This case is troublesome merely because the car has been reclassed. Yea, that's the dick sandwich! Now, lots of guys, (Like Dave Gran) jumped up for joy when they got reclassed. But others who are racing on true shoestrings, find the change troublesome. Usually, there is revenue to be gained from the sale of the old 7" rims to ITA drivers...but, in some cases, the car is so unique the rims have no market. (offset, bolt patter combos)

For this specific reason, I'd support a dual listing of the car for a certain period, say three years.

Otherwise, the needs of the many outweigh the needs of the few. And the many already have 8 - 16 rims in the 6" width, plus tires, etc. To change over the entire class is excessive.

Also, Rojer, I can not remember any member of the ITAC stating that there is no difference in performance potential between the widths, or anyone stating that it didn't matter, as you suggest.
 
One thing that I am absolutely against would be some sort of spec line allowance. If a change is made, make it for the whole class.

I can see the argument for a 'sunset' period when a car is moved from A to B that allows dual classification.

Also, if a change were made under the guise of availability of products, it should move right to 7", not 6.5". While 6.5 is pretty common for 15" wheels, and obtainable in 16" wheels, the majority of the C and B cars are on 13 and 14, and I don't ever see 6.5 wide versions of those.
 
One thing that I am absolutely against would be some sort of spec line allowance. If a change is made, make it for the whole class.

I can see the argument for a 'sunset' period when a car is moved from A to B that allows dual classification.

Also, if a change were made under the guise of availability of products, it should move right to 7", not 6.5". While 6.5 is pretty common for 15" wheels, and obtainable in 16" wheels, the majority of the C and B cars are on 13 and 14, and I don't ever see 6.5 wide versions of those.

Any line-item exemption or allowance is going to be a very hard sell under current practices.

Like Josh, I'm sensitive to the fact that drivers' lives get complicated by class change. That whole business is complicated because when something like the MR2-to-B initiative gets proposed, there's always folks advocating for both choices - moving and not moving. If we get a request for a move and it makes sense based on our practices and processes, should we do it simply because it looks right on paper? Or should we lean heavily on input letters from drivers? From only those owning examples of the car getting moved...?

The same kind of conflict extends to other follow-on options like grandfathering in 7" wheels or allowing dual classification for cars that get moved. Do we then entertain any and all requests for moves, knowing that each will come with those same allowances? Do we grant the allowances more broadly when someone makes a pitch that, regardless of the circumstances that led to the situation, having 7" wheels is perceived as a competitive advantage?

PERSONALLY I feel very strongly that upsetting the category apple cart with special cases must be done VERY cautiously, for a lot of reasons - Number One being that the members tell us that consistency is a favorite aspect of IT.

K
 
Kirk, I'm with you. And on your last point, the entire aspect of stability is what I think both you and I hear as the "big thing" (along with the not too much, not too little ruleset) that attracts and keeps drivers and owners to IT.

And for that reason, I think allowing dual classification (as in the case of the E36 in ITR and ITS) is warrented when there are material changes that need to be made to the car to switch classes.

This car is a good example, and if I were king, my policy would be to extend 3 years "granfathering" of dual classification for any car that got moved across the ITB/ITA line, or the ITS/ITR line. Of course, I'm not talking about taking your ITA wheels and running ITB. You want your 7"-ers? Run in ITA. You want to be in ITB? Get the rims.
 
So I could run ITA on 7's and ITB on 6" wheels and double dip...

Or since the wheel widths are maximums, I could run both on the narrower wheels.

And if I want dual classification for my marginal/tweener car I could request that it be moved. I know what the Golf III would have to weigh in ITC and since I'm overweight in B, I'm part way there.

All kinds of interesting options!

K
 
Interestingly, we're partly there now. SMs, as you know, are douple dipping more often than George Costanza at a party when he hasn't eaten for an hour.

But, they aren't ITA cars, are they? IIRC there are some minor technical issues that make them technically illegal for ITA. Yet, as Josh will attest, I saw 45 of them run at a Sears Point...errr Infineon...race a couple years ago. And ther were 7 actual ITA cars. It's up to the class regulars to decide if that's "OK" or not, and discuss as needed.

(Of course, if there's one guy who's got issues, he's got a lot of paddock walking/talking to do!)
 
For purely selfish reasons I would like to see 7" in ITB, since the car I am building came OEM with 14 X 7 wheels:shrug: Chuck

I've always found the width difference between classes to be silly. But, I've been around long enough to understand the historical significance ("back then", we couldn't change diameter, and the vast majority of the cars in the 70's and 80's that fit into ITB/C ran 13" wheels -- 14" if they were "high performance". And 6" width at the time was pretty much 1) all you could get in that diameter at a reasonable price and 2) all you could fit inside the fender wells of those cars -- most cars had 175 or 185 as stock section width...)

I've never been opposed to opening that 7" limitation to ITB and ITC; honestly, the only real opposition to that idea has historically come almost exclusively from competitors in ITB and ITC that already have 6" wheels....purely coincidental, I'm sure ;)

GA

P.S. For purely selfish reasons I now have an ITB car with a 4x114.3 bolt pattern, and I'd REALLY like to stay with 14" wheels, given the wheels and tires are roughly 7-8% of the car's total weight (if you know of a source for "reasonable" weight 14x6 wheels - see, I'm not even trying to be totally selfish by asking for "light" weight - in that bolt pattern at a reasonable price, I'm all ears...) :shrug:
 
16 wheels.....that's 4 sets. no wonder some are reluctant to a change.
I think the answer might be in this question: All of the Miata drivers that now run ITA; if you were reclassified to ITB, not IF but WHEN, what would you want the rules to be?

You are now running with 7". you have all your data based on 7" and now you have to unload your useless 7" rims (because ITA has probably allowed 17 X 8 in ITA) and buy 16 rims in 6" and then recalc all your data. It will happen as newer cars enter ITA and cars become reclassed.

Think about that and try to figure what is best for the class or better yet what is best for IT.

Dual classisfication might be ok if ther were weight allowances, but then that might null the reasons for reclassification.

The better answer is to allow any width based on fender clearance regardless of class and move on.

I do understand some concerns about the $ impact to some racers, given current inventory,etc. But the best answer for every car regardless of class is a rim width based on fender clearance. No restriction on diameter. a rule such as that wold be undisputable and continue to serve all It racers based on the car they built today, 30 years ago, and five years from now. (my opinion only)
 
I think the answer might be in this question: All of the Miata drivers that now run ITA; if you were reclassified to ITB, not IF but WHEN, what would you want the rules to be?

Rodger, while I agree with your conclusion (in fact I told the ITAC the same thing a few months ago), I don't agree with the way you got there. There's no reason to believe that ITA Miatas will ever be reclassed to ITB. As far as the ITAC is concerned, the speed of each IT class is "fixed" based on power-to-weight ratio. Faster cars won't get added to ITA forcing existing cars to move down.

The reason why your car got moved down is that at the time its classification was done, there was no power-to-weight system for IT. Classing in IT was haphazard and inconsistent. Now that there's a system, it makes sense to move your car to where it fits correctly, so it can actually compete for a win. And, it was done in response to member input, and it was all weighed carefully.

But anyway, I agree with your conclusion, any size wheel makes more sense than what we have now, since we already have restrictions on fender modifications, and we have require the tire to fit under the fender. Good enough for me. But the argument against, and it's a good one, is that people who already own multiple sets of narrower wheels than they could fit will feel that THEIR investment in wheels is now for naught. And they are right, wider *is* better, even for the same size tire, in most cases. It's a tough pickle. Sometimes leaving well enough alone is the best answer, since we are not starting from scratch.
 
Think about that and try to figure what is best for the class or better yet what is best for IT.

What’s the availability of inexpensive 13” and 14” diameter rims with a 7” width? I admit that my search was very quick but everything I came up with were 6"s wide. (Primarily looked at Tire Rack.) I can't help but think that this could create a new problem of people not being able to source replacement 7" rims at a reasonable cost.


any size wheel makes more sense than what we have now, since we already have restrictions on fender modifications, and we have require the tire to fit under the fender.

Now you'd be impacting the entire category. :( Since some cars will have the ability to stuff a larger rim / tire within the rules, shouldn't that impact the classification process as well?

I wouldn't be surprised if I could get 8" wide rims to work on my car where others have a tough enough time with 6" rims.
 
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Some random thoughts as I keep thinking about the issue.

The one point that gets made and forgotten each time we have this conversation is that the only people that are FORCED to get new wheels are the ones moved from A to B, because the 7" stuff they have is no longer legal. If the rule were changed to allow A,B,C,S to all use 7" wheels, NO ONE would be forced to replace their wheels, as the 6" stock would still meet the rules. In that light the least disruptive choice is to go wider.

Playing devil's advocate to my own current position on the matter...

Of course wider wheels beget wider tires, which alters the detriment that each pound creates in a sprint race. You could reduce the impact of higher spec line weight, to a point, with more tire - especially on a fwd car. Would this upset some balance of the class?
 
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