Wheel diameter rule change Poll

[Knestis]

Actually no, you are wrong. The reason this question has been brought up - and I have done so repeatedly - is that it is all but impossible to find 14x7" wheels. When I was planning on an ITA Honda, I did a LOT of shopping around - to no avail.

Now that I'm headed to ITB, it's not a personal issue for me since I can find a variety of 14x6" wheels - at least for now. That doesn't mean that I don't think it is a sensible option to consider making the change.

K

 

[Geo]

Originally posted by Super Swift:
Geo- Cheap. Solid. Bushing. nuff said. Opinions differ and that’s life.

Most correct. Reasonable people can disagree. I'm with you on that.

As for cheap? Only if you can machine the cassettes yourself. Or, if you are lucky enough to find a bearing that will fit (without modification) inside the control arms. Not likely. Otherwise, you have to have cassettes machined to hold the spherical bearings. Easy for a real race shop. IMHO, not in the spirit (or philosophy) of the IT rules.

But, I do agree that reasonable people disagree. Besides, there are still people who think RR dampers belong in IT.

Of, and FWIW, I am designing spherical bearing cassettes for my 944 and my business partner's Sentra SE-R. I just think it's nuts.

------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com

 

[TypeSH]

Originally posted by Knestis:
Actually no, you are wrong. The reason this question has been brought up - and I have done so repeatedly - is that it is all but impossible to find 14x7" wheels. When I was planning on an ITA Honda, I did a LOT of shopping around - to no avail.

It is not impossible to find 14x7 wheels, they are available but they are expensive. Allowing a wheel diameter change would help reduce the costs of racing for those who want to go this route, which I am all for. Similarly I would like to run 15" wheels instead of the mandated 16" to save money. Sticking with my same make and model of wheels and tires, it would save me about $100 a set of rims and $80 a set of tires. To me this only fair solution is to allow a move up OR down in size.

 

[theenico]

Originally posted by Super Swift:
Geo- Cheap. Solid. Bushing. nuff said. Opinions differ and that’s life.

Here's a link to cheap monoball housings/heim holders. The most "expensive" one is $16.00

http://www.ubmachine.com/page24.html

Some will fit with no mods and some may need the OD turned down, but I was still able to convert my Scirocco for less than half of what Shine wants.

Back on the original topic, I believe that wheels should be allowed in any diameter (no "dubs with floss" please

) and widths to be no greater than 7" for everyone.

Is anyone else getting tired of Fast & Furious kids asking us if we want their stock wheels

With a lot of the IT cars being classed in limited prep production wouldn't it be nice to have the option of jumping over without having to buy more wheels. Of course Avon does make a fairly mediocre 14" slick for us.

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Nico
KCRaceware (816) 257-7305
[email protected]

[This message has been edited by theenico (edited October 07, 2003).]

[This message has been edited by theenico (edited October 07, 2003).]

 

[Knestis]

If you have an FnF'r offer you 14x6 alloys off of any MkIII VW, take 'em - I pay shipping to get them to me, where they can do some good...

Kirk

EDIT - 4x100 pattern, please!

[This message has been edited by Knestis (edited October 07, 2003).]

 

[Geo]

Originally posted by theenico:
Here's a link to cheap monoball housings/heim holders. The most "expensive" one is $16.00

http://www.ubmachine.com/page24.html

Some will fit with no mods and some may need the OD turned down, but I was still able to convert my Scirocco for less than half of what Shine wants.

Great link. But, it's also only applicable to a portion of the application. What do you do for the trailing pivot on the control arm? And what do cars with IRS do? The bottom line is a full set of spherical bearing cassettes are not cheap. Most need to be custom-made. That sounds more like what belongs in Production than IT to me. Philosophically I don't think they fit in IT.


------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com

 

[Banzai240]

Originally posted by Geo:
And what do cars with IRS do?

I'll tell you what I have to do... I have 5 links on EACH SIDE in the rear... times 2 bearings per link.... AAAAAARRRRRRGGGGGGHHHHH...... one.... two... threee... oh, there's a dime, fourteen... fifteen... sixteen...

------------------
Darin E. Jordan
SCCA #273080, OR/NW Regions
Auburn, WA
ITS '97 240SX

 

[Geo]

Originally posted by Banzai240:
I'll tell you what I have to do... I have 5 links on EACH SIDE in the rear... times 2 bearings per link....

Plus one cassette per end of each link that must be custom-made at what, $25-50 per cassette? Minimum.



------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com

 

[SamITC85]

Okay a couple of comments. First off with this rule change the 16 13x6 wheels I own are now obsolete in IT, plus I really doubt that I could fit anything much bigger than a 14" rim on my ITC rabbit without changes legal to IT, maybe I could but I doubt it. Secondly it was brought up that bigger wheels would allow easier transition to Prod, not true at all. I believe the largest wheel in G and H prod is 14 inches, so allowing an ITC or ITB competitior 15 inch wheels is not going to make an easy crossover to prod. This rule is going to cost me and a lot of ITC and B guys a lot of money that we have already invested in wheels and tires. Because of this I am not so sure this is the way to go, plus I can find a lot of 13x 5.5 wheels fairly easy, 14" are a different story I agree, and for that my solution would be to allow 13" wheels, as well, I know the ITB Golfs have that option. Anyway just my .02 worth

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Sam Rolfe
TBR Motorsports
#85 ITC VW Rabbit
#85 GP Scirocco on the way
#11 GP Scirocco on the way

 

[Banzai240]

Originally posted by SamITC85:
Okay a couple of comments. First off with this rule change the 16 13x6 wheels I own are now obsolete in IT...

I would love to hear the rational behind this statement...


------------------
Darin E. Jordan
SCCA #273080, OR/NW Regions
Auburn, WA
ITS '97 240SX

 

[SamITC85]

Obsolete may have not been the best word, but I do believe that their will be a performance advantage to anyone who runs a 15" rim on their car. Which means if i want to compete I need to get new wheels.

 

[Greg Amy]

I would strongly disagree, Sam. 13" wheels (v 15" wheels) are:

- lighter
- smaller circumference
- stronger

The *only* viable reason for running larger diameter wheels is:

- required by the rules (e.g., WC runs 17")
- gotta fit larger brakes under there
- more variety in wheel choice
- more variety in tire choice
- want to look "bling"

I run 14x7 wheels on my ITS car, and I've already got 6 good wheels. If these guys are successful in getting an open diameter I won't be buying any 15" wheels until the day the good tires are no longer available in my size.

Nope, Sam, I fail to see any downsides to this, really. Let your competitors tack on an extra 5 pounds per wheel and increase their rolling circumference. You can smile as you accelerate right by 'em...

Greg

 

[SamITC85]

Greg you may be right, I will be accelerating by them but in an ITC car at somewhere like the glen, pocono, Road Atlanta, Mid Ohio or any track with a long straight the 15 inch wheel will generate a high top speed and go by me buy the end of the longer straights. Also I was more trying to play devils advocate more than anything.

------------------
Sam Rolfe
TBR Motorsports
#85 ITC VW Rabbit
#85 GP Scirocco on the way
#11 GP Scirocco on the way

 

[Geo]

Originally posted by grega:
I run 14x7 wheels on my ITS car, and I've already got 6 good wheels. If these guys are successful in getting an open diameter I won't be buying any 15" wheels until the day the good tires are no longer available in my size.

Or, until you bend 3 wheels since your wheels are NLA because you could buy at least two full sets of 15" wheels for what a set of 14x7 Panasports run (assuming they remain available).

------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com

 

[Banzai240]

Originally posted by grega:
- more variety in wheel choice
- more variety in tire choice

Thank you for supporting the argument FOR this change...

<font face=\"Verdana, Arial\" size=\"2\">I run 14x7 wheels on my ITS car, and I've already got 6 good wheels. If these guys are successful in getting an open diameter I won't be buying any 15\" wheels until the day the good tires are no longer available in my size.</font>

NICE to have options, though, isn't it!!??

Nope, Sam, I fail to see any downsides to this, really. Let your competitors tack on an extra 5 pounds per wheel and increase their rolling circumference. You can smile as you accelerate right by 'em...
Greg

And then those of us with 16" wheels will smile as we corner right by you!!

Seriously though... There really isn't a down side to this, and as you can "see" (read), there are as many arguments as to why there ISN'T an advantage as to why there might be. The bottom line is that it would give everyone POPULAR options, which makes racing CHEAPER from an equipment standpoint...

Somebody needs to start writing those letters, however...

------------------
Darin E. Jordan
SCCA #273080, OR/NW Regions
Auburn, WA
ITS '97 240SX

[This message has been edited by Banzai240 (edited October 07, 2003).]

 

[Bill Miller]

Well Darin, I think there is a downside. If you open things up and start allowing all the IT cars to run 15" wheels, I can see the tire mfg's going the way of the wheel mfg's and offereing less and less in 13" and 14" (does Hankook have any plans of offer 13's or 14's?). That hurts the guys that currently have large inventories of 13" and 14" wheels as they'll have less tires to choose from, or they'll have to pony up money for new wheels and will have 13" or 14" wheels that will really have no value to anyone anymore (and that includes the Panasports/Revolutions/etc. that people have already bought).

As far as Prod goes, there aren't many (any?) cars in HP that can run 15" wheels, but several (most) of the GP cars are allowed 15's.

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

 

[Greg Amy]

<font face=\"Verdana, Arial\" size=\"2\">Thank you for supporting the argument FOR this change...</font>

C'mon, Darin. I think you're becoming far too gun shy lately.

I personally don't give a rat's ass about this rule, as in my mind I've currently got the perfect wheel size in terms of performance. I was simply pointing out to Sam that larger diameter wheels - given everything else equal - are a performance disadvantage.

Maybe not everything else is equal, but that's irrelevant to my point.

<font face=\"Verdana, Arial\" size=\"2\">...will smile as we corner right by you!!</font>

Darin, you explain to me how a 225/50-13 tire is in any manner faster or corners better than a 225/50-15 and I'll concede your point. However:

225/50-13 Hoosier
8.3" tread width
21.8" diameter
68.5" circumference
9.1" section width

225/50-15 Hoosier
8.2" tread width
23.4" diameter
73.6" circumference
9.0" section width

The 13" wheel and tire combination is clearly superior in terms of track performance. It's lighter, stronger, and has 7% less rolling diameter. Hell, it's like moving from a 3.81 final drive to a 4.2!

Considering all unintended consquences, I guaran-damn-tee you that if the wording allows it, you'll see people going DOWN in wheel diameter. I would if I could.

Greg

 

[Banzai240]

Darin, you explain to me how a 225/50-13 tire is in any manner faster or corners better than a 225/50-15 and I'll concede your point. However:

225/50-13 Hoosier
8.3" tread width
21.8" diameter
68.5" circumference
9.1" section width

225/50-15 Hoosier
8.2" tread width
23.4" diameter
73.6" circumference
9.0" section width

The 13" wheel and tire combination is clearly superior in terms of track performance. It's lighter, stronger, and has 7% less rolling diameter. Hell, it's like moving from a 3.81 final drive to a 4.2![/B]

Time for class:

Given a 15" wheel option... why would I run a 225/50ZR15. Class? Bueller???

Answer: I wouldn't!

I would choose the following:
Hoosier A303 - 225/45ZR15 specs:
Section Width: 9.3"
Tread Width: 8.6"
Diameter: 22.8"
Circum: 71.63"
SIDEWALL HEIGHT: 3.9"

You are leaving out one VERY important factor... SIDEWALL HEIGHT...

Using your examples...

225/50ZR13 Sidewall Height: 4.4"
225/50ZR15 Sidewall Height: 4.2"
225/45ZR15 Sidewall Height: 3.9"

So, this aspect alone makes the 15" wheel/tire combo, even in your example, a superior tire from a performance/stability standpoint. Shorter sidewall means less flex which means more stable contact patch.

So, even though your 13" combo may have a larger tread width compared to your original example, less of that tread is staying in contact with the pavement because your sidewalls aren't stable enough to keep it there...

NOW, add the option of using the 45 series 15" tire instead, with a sidewall that's 1/2" shorter than YOUR 13" sidewall AND has a .3" MORE tread width, and the answer is clear... The effects of gearing (4% taller for the 15") can be compensated for with rear gears... but it likely wouldn't need to be, because off the following:

Larger diameter wheel + shorter sidewall + larger contact patch means more stable sidewalls + less flex means more contact patch remains in contact which translates to better handling which gives higher exit speeds which yields faster straightaway speeds which negates the need for lower gearing which equates to me kicking your ass!

Class dismissed...

OH wait... before you go... One more thing... the slightly higher mass of the 15" combination absorbs more heat than the 13" combination, which helps to keep the tires under the car longer, as does the larger rolling diameter, which gives the rubber more time to cool between contact...

("gunshy"???

)

------------------
Darin E. Jordan
SCCA #273080, OR/NW Regions
Auburn, WA
ITS '97 240SX

[This message has been edited by Banzai240 (edited October 09, 2003).]

 

[Greg Amy]

I see your points, but I still disagree in the end result.

However, since you've "proven" there is most definitely a distinct performance advantage to allowing larger wheels then I would really, really hate to allow a modification that would, at a single stroke, immediately nullify the investment of all current wheels in use. Therefore, on this premise alone, I will vigorously and actively oppose the adoption of a rule that would allow IT cars to use any wheel other than the stock, listed diameter.

Thanks, Teach.

 

[Banzai240]

Originally posted by grega:
I will vigorously and actively oppose the adoption of a rule that would allow IT cars to use any wheel other than the stock, listed diameter.

Whatever... Just remember that there is bound to be someone out there (George???) who has just as many reasons why the larger diameter combination is NOT a performance advantage... I doubt that 5% of us IT drivers out there would even have the money or the talent both come together at the same time to even tell the difference...

The point is to make this class less expensive overall, and allowing a more popular tire/wheel package means there is more supply, which means less cost... I'd take that over any performance advantage/disadvantage, perceived or otherwise... The short-term discomfort for some does not justify ignoring the long-term health of the class...



------------------
Darin E. Jordan
SCCA #273080, OR/NW Regions
Auburn, WA
ITS '97 240SX