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View Full Version : What width tires do you use with your 6" rims?



gran racing
12-18-2004, 06:17 PM
I've heard a bunch of people that use 225 Hoosier tires on their 6" rims, which really surprised me. I realize that it may be possible to stuff them on to the rim, but I have a hard time believing that is the optimum size.

So I'm curious, what width Hoosier tire do you use. (I am specifying Hoosier tire because their 205 is like a Kumo or Toyo 215)

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Dave Gran
NER ITB #13
'87 Honda Prelude si

racer_tim
12-18-2004, 06:56 PM
Dave, from Hoosier's web site, the 225-45-13 needs a 7.5" rim and the 225-50-13 needs a 7" rim

http://www.hoosiertire.com/rrtire.htm



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Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

Bill Miller
12-18-2004, 07:41 PM
I've seen 225/45 and 225/50 13" Hoosiers on 6" rims. I knew a guy that used to run an ITC Scirocco that ran the 225/50's (I think Dave Parker bought the car). I've also seen 2002's w/ them on 6" wheels. Seems to be a tad much tire, if you ask me.

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

racer14itc
12-18-2004, 11:31 PM
I ran the 225/45-13's on my ITC Scirocco. It looked like too much tire to me too. Prior to that I ran the 185/60, the 205/60, and 225/50 series. However, the 225/45 was the fastest on the stopwatch.

The tire busters didn't care much for trying to stuff that much tire on the rim, and the tire wore funny (a strip about 2" wide about 1/3 of the way from the inside edge...mostly on the RF) but it was faster so that's what I ran.

Interestingly, the 185/60 all around was almost as fast at VIR (probably due to less rolling resistance), but I would run out of front tire late in a race (over heated them). My setup on the ITC Scirocco was the 225's out front and the 185's in the back, if anyone cares... http://Forum.ImprovedTouring.com/it/smile.gif

MC

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Mark Coffin
#14 GP BSI Racing/Airborn Coatings/Krispy Kreme/Tristram's Garage VW Scirocco
http://pages.prodigy.net/Scirocco14gp

wbp
12-19-2004, 12:58 PM
The 225 Hoosier may seem like too much tire fo the 6 inch rim, but that's what the front runners in ITC at the ARRC were wearing. Works fine if you control camber properly.

JohnRW
12-20-2004, 12:38 PM
The Volvos are running 225's on a 6" rim. Eat your Wheaties before you turn on the mounting machine.

dave parker
12-20-2004, 02:33 PM
Oh this is a great topic.
I think this comes down to two things, setup and driving style.
I have no great words of wisdom on this.
I did buy a ITC Scirocco (from Jay Frye) that had 225/50/13 tires on it (goodyears if i remember)they were pretty worn but worked good for my first three races.
I bought another ITC Scirocco (from David Massi but built by Mark Coffin) that came to us with 205/60/13.
Ted the hoosier man has told me that all of these tires are too big for a 6 inch rim. His recommendation was the 185/60/13 for a six inch rim.I guess I will be trying that size next.
I still think that there can be TOO much rubber under these low horsepower cars. But what do i know?
cheers
dave parker
WDCR ITC#97

[This message has been edited by dave parker (edited December 20, 2004).]

gran racing
12-20-2004, 07:56 PM
<font face=\"Verdana, Arial\" size=\"2\">I think this comes down to two things, setup and driving style.</font>

Driving style - could you expand on this one? And of the different driving styles you are talking about, which suits each selection better?

Everything mentally tells me to use the 205/60 tires, but seeing some of the front runners using the 225 makes me think a bit. I know, just because they are doing it doesn't mean that is the fastest.

I was also hoping to benefit by the gearing of the 45 tire versus the 60.


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Dave Gran
NER ITB #13
'87 Honda Prelude si

dave parker
12-21-2004, 04:36 PM
Dave
"Driving style - could you expand on this one?"
I guess the best way to describe it is do you like the car "loose" a tendency to oversteer or do you like the car to feel "planted" to the racing surface.

As has been discussed here many times loose is fast, or as Don Barrack (probably one of the best instructors out there) says "If you have enough real estate you can drive out of any oversteer skid. But if you are understeering (e.g. pushing or turning the wheel and nothing is happening) you have to lift."

The balance that has to be created here is how loose do you want the car coupled with the other important factor that you mentioned in your last post using the tire to complement your gearing. It is a question that can only be answered by the individual driver through testing, preferably not on a race weekend.

As I said before I have no great words of wisdom on this subject.

Are you confused yet? I know I am.
cheers
dave parker

badal
12-21-2004, 05:42 PM
I agree with wbp.
Copy the fast guys.
Oh, and Tim, read the fine print:
* MEASURED RIM
THE TIRE AND RIM ASSOCIATION MANDATES A SPECIFIC RIM WIDTH FOR EACH TIRE SIZE SO THAT DIMENSIONS FROM VARIOUS MANUFACTURERS CAN BE EQUALLY COMPARED. PLEASE REFER TO THE "RECOMMENDED RIM" INFORMATION FOR THE BEST PERFORMANCE RESULTS.

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"Bad" Al Bell
ITC #3 Datsun 510
DC Region MARRS Series

Al Seim
12-21-2004, 05:59 PM
I think that there are a lot of factors at work here. I strongly suspect that if Hoosier offered a really low profile 205 it would be the perfect tire for an ITC VW and probably other 13 x 6" cars. I think that the 185 is too narrow, the existing 205s too tall, and the 225/45 too wide but "least wrong".

I tried the 225/45 Hoosiers on my ITC car this past year. One fear I had did not prove to be true - steering response and feel were fine, I guess the short sidewall made up for the narrow bead in terms of carcass stiffness. Couldn't compare times as I hadn't driven in 4 years so was rusty as all getout.

BTW, the fastest ITC car (champion anyway)at Summit Point MARRS this year was on 225/60 Hoosiers.

One other tidbit - Hoosier told me that the rim recommendations are from industry standards for that section width and not really meaningful in a racing context.

Good Luck!

Al Seim
Action Digital Race Data Systems
www.actdigital.com (http://www.actdigital.com)

gran racing
12-21-2004, 06:26 PM
What about tire wear? I would imagine the 205 would wear better then the crammed on a rim 225.

Any thoughts / experience?

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Dave Gran
NER ITB #13
'87 Honda Prelude si

DENIS SCHEMBRI
12-21-2004, 08:04 PM
the 225-50-14 will fit on the 6" rim but be ready for a fight the 205-55-14 will fit better but they are apx. 1.5 inches narrower with the same height no real scientific testing here but but i believe the 205,s were quicker not a big difference but since i mount my oun tires on a manual machine i will be using 205,s when these wear out ( it-b dodge charger) the 205,s also fit better under the fender well the 225,s are a tight fit just my 2 cents hope this helps