ITR WHEEL SIZES

Grafton/Dan, would one of you guys help me with filling in the last gaps on the BMWs on the ITR ITCS chart? I'm way behind on getting those to Andy/ITAC and having some trouble with the Bimmers.

Thanks guys. [/b]



Jeff, I have the BMW Tech manuals on my computer. I'll try and fill in the blanks for you.
 
I already sent everything to him except for the E30 M3. But feel free to check my work. I found that the brake rotor sizes were wrong for pretty much everything, not to mention the 6-speed listing for the Z3.
 
I already sent everything to him except for the E30 M3. But feel free to check my work. I found that the brake rotor sizes were wrong for pretty much everything, not to mention the 6-speed listing for the Z3.
[/b]

Cool, thanks
 
Thanks guys.

Need help with the 635 as well. Not sure anyone will build one, but would be cool if they did. Don't have much on it (see GCR). DAn, you have a manual for that car?

Thanks again.
 
Thanks guys.

Need help with the 635 as well. Not sure anyone will build one, but would be cool if they did. Don't have much on it (see GCR). DAn, you have a manual for that car?

Thanks again. [/b]



I should as soon as I get a chance to get to my computer I'll check and I'll let you know one way or the other.
 
ITAC, R committee, I really think this is a bad idea to let this BMW 18" wheel thing sit as is. I do not know definitively if any other cars in R have 18" wheels as an option. In fact, I'm not sure the BMWs have the option either - that is as a real option when the car is built, not as a dealer installed item. I'm sure the BMWs had it as a dealer installed item as BMW has plently of bling running around in the showroom and parts counter here in NC.

Either way, it'll be hard to document this as fact and I think what will happen is that the BMWs are going to have something different than the other cars in ITR, i.e. 18" wheels and we're going to see something similar to the E36s fiasco that we saw in ITS (hate to bring that up again). Seems the logical thing to do is cap it at 17"x8.5" and avoid the issue all together.

Ron
 
If any cars were/are/will be available with 18" wheels as DELIVERED from the factory - no dealer-installed stuff - on an ITR-eligible car as delivered, then I think we have an obligation to allow them. That standard should also define the diameter listed in the ITCS.

K
 
I agree w/ Kirk. If the car came w/ 18" (or larger) wheels AS STOCK, they should be allowed (but nothing wider than 8.5", regardless of stock width). The cars are new enough, that it shouldn't be that hard to find out stock sizes. And I think it needs to be listed on the spec line.
 
Allowign the stock diameter is consistant with current philosophy, and I suppoert it.

As it is, there are occasional issues with larger than "Stock" requests, and the ITAC has handled those, so I see no reason it can't handle a few more.

Stock=factory equipped = OK
Dealer equipped, even if it's a factory part, = Not OK, unless it was available on the car when it came on the boat from the factory,
 
Allowign the stock diameter is consistant with current philosophy, and I suppoert it.

As it is, there are occasional issues with larger than "Stock" requests, and the ITAC has handled those, so I see no reason it can't handle a few more.

Stock=factory equipped = OK
Dealer equipped, even if it's a factory part, = Not OK, unless it was available on the car when it came on the boat from the factory, [/b]



As long as your not going to allow the width to be more than 8.5", I can handle this too.
 
If any cars were/are/will be available with 18" wheels as DELIVERED from the factory - no dealer-installed stuff - on an ITR-eligible car as delivered, then I think we have an obligation to allow them. That standard should also define the diameter listed in the ITCS.

K
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Ok, I can see that, but the cars that can have those will be speced in the line for that car, correct?

Ron
 
Just as all the rest are, I would sure hope so. Someone shows up with wheels bigger (or smaller!) than allowed by their spec line in, say ITA, it doesn't matter what kind of case they can make at the track.

K
 
.... I do not know definitively if any other cars in R have 18" wheels as an option. In fact, I'm not sure the BMWs have the option either - that is as a real option when the car is built, not as a dealer installed item. I'm sure the BMWs had it as a dealer installed item as BMW has plently of bling running around in the showroom and parts counter here in NC.

Either way, it'll be hard to document this as fact and I think what will happen is that the BMWs are going to have something different than the other cars in ITR, i.e. 18" wheels and we're going to see something similar to the E36s fiasco that we saw in ITS (hate to bring that up again). Seems the logical thing to do is cap it at 17"x8.5" and avoid the issue all together.

Ron
[/b]

Ron a Simple google seach turned up this Car&Driver article:

Car & Driver Test of 330i PP

I'd know of the perfromance package because I saw a few for sale while we were looking for my wife's 330, as well as auto-crossing aginst one with my street Z3. Unless someone wants to pony up the big bucks for BBS rims I doubt any good light weight 18" rims exist. My friend with the 330 PP would swap out for 17" Kosi's with Kumho's.

James
 
Also, does wheel diameter really matter that much from a performanced perspective? Width is what we car about; wheel diamter is mostly just cheap gearing right?
 
Also, does wheel diameter really matter that much from a performanced perspective? Width is what we car about; wheel diamter is mostly just cheap gearing right?
[/b]

Right....

Tests have shown that all other things equal, going to the largfer size wheels can actually hurt performance.

As a matter of fact, SUVs that get the "upgrade" from say 18" rims to the big 20" rims, (with low profile tires) end up handling worse, riding worse, and the really bad part, they take longer to stop from 70MPH...lots longer.

Also, I've read a number of times now that auto writers prefer the smaller rims on certain cars over big rim option packages, for a variety of reasons, some of which are performance based.

And yes, no matter what, ITR max width is 8.5", max diameter is 17" or whatever came stock if that's greater than 17".
 
Ron a Simple google seach turned up this Car&Driver article:

Car & Driver Test of 330i PP

I'd know of the perfromance package because I saw a few for sale while we were looking for my wife's 330, as well as auto-crossing aginst one with my street Z3. Unless someone wants to pony up the big bucks for BBS rims I doubt any good light weight 18" rims exist. My friend with the 330 PP would swap out for 17" Kosi's with Kumho's.

James
[/b]

I assume from the article, that package was available on the 2004 models. Even more interesting than the wheels are the "hotter cams" and six speed transmission. Since they were optional equipment they will be legal unless noted otherwise if that year model is included in the spec line later on, along with the already mentioned 18s.

Grafton
 
Allowing the stock diameter is consistant with current philosophy, and I support it.
[/b]

If any cars were/are/will be available with 18" wheels as DELIVERED from the factory - no dealer-installed stuff - on an ITR-eligible car as delivered, then I think we have an obligation to allow them. That standard should also define the diameter listed in the ITCS.

K
[/b]


Just to keep the record straight, it may be current philosophy or percieved obligation as pertains to ITR, but it has not always been the philosophy that IT used. Case in point, when I first started running a second gen RX7 in ITS I had a conversation with (I think it was) Bob Burns about the 89-90 GTUs model came from the factory with 16" wheels and weren't they legal although they were not listed on the spec line. He said no and the reasoning was that "everybody with an RX7 would need, or think they would need, to buy 16" wheels."

Lo and behold, the GCR the following year had a specific mention in the spec line saying no 16" wheels.
Now I have to say, that's the quickest service I every got from "Central Office", especially since I didn't "write a letter" :lol:
 
Thats a very good point, yet the ITCS list is litterally littered with cars that list stock diameter as "15 or 16 inches". In the RX-7s case, it was decided to make the GTU guys buy smaller, rather than allow the non GTU guys to opt to a larger dimeter....hmmm.
 
OK, just to be perfectly clear for those that are not too familiar witht he RX7's various models, there was in 1989 and 1990 a limited production model called the GTUs which is different than the many other years models called GTU. That is the only non-turbo model that came with 16" wheels, but one of the other features was a closer ratio 5th gear which is a very common upgrade in all 2nd gen cars.
I'm not wanting to :dead_horse: , just adding some insight, which I have very little of. :wacko:
 
OK, just to be perfectly clear for those that are not too familiar witht he RX7's various models, there was in 1989 and 1990 a limited production model called the GTUs which is different than the many other years models called GTU. That is the only non-turbo model that came with 16" wheels, but one of the other features was a closer ratio 5th gear which is a very common upgrade in all 2nd gen cars.
I'm not wanting to :dead_horse: , just adding some insight, which I have very little of. :wacko:
[/b]


I'm not a Mazda guy by any stretch of the imagination, but wasn't the GTUs also a bit lighter? I seem to recall that it was more of a 'Club Sport' type model (less extra BS, more track-ready). I thought I heard once that none of the GTUs cars came w/ power windows or AC.
 
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