I would agree with you if this were bench racing. however the same logic was proven wrong by a large margin on past occasions with 225's. Every 225 I have tried was faster when mounted on a rim nearly an inch wider than the tire manufacturer recommended. So I won't take anybodies word on this subject based on this logic without some credible people actually trying it.

Bob

It's all bench racing till proven otherwise. The are many variables different than with the 225's.

I for one look forward to seeing some actual data.

Plenty of data on every other tire out there - wider is faster.

205 NT-01 on 7 vs 8 - 8 is faster
205 R6 on 7 vs 8 - 8 is faster
225 nt-01 on 8 vs 9 - 9 is faster
225 R6/A6 on 8 vs 9 - 9 is faster
225 RS3 on 8 vs 9 - 9 is faster

IIRC CoralDoc in Florida said that a couple of the folks down there have run a 205 Hoosier R6 on a 9" wheel and said it was better than the same tire on an 8" wheel (also said that the 205/50 R6 had a wider tread patch than a 225/45 RA1, both on 8" wheels).

The definition of insanity is doing the same thing over again and expecting a different result.

Your argument:

The aero is worse with a 10" wide wheel, and this aero penalty will outweigh the benefits of the wider wheel (namely improved traction on corner exit)

My rebuttal:

https://www.miataturbo.net/attachmen...ine=1315957057

Guys keep in mind all of your examples are from DOT-R tires. We are talking about a true racing slick here with VERY stiff sidewalls. I have played with LOTS of slicks on other marques so even though I have a low post count I am not exactly a newbie.

Stay open to what I am saying and let the results speak for them self. Nothing to be gained by taking such a firm stance on the matter one way or the other.

Anybody running this amount of tire and spending this much money should have already incorporated a splitter, wheel spats, and canards.

///STFU and post data if you want to continue the argument, and post an into thread or I'll have you banned

Nice attitude!

Go for it.

I see you changed your first response. It was a intelligent debate until you piped it. No need of wasting my time here if that's the attitude.

I have customer that built a Miata something like this. His solution to the roll center problem was to sorta channel the tub and lower the body on the frame rails. Has to be a class that allows that but I think it might be the easiest way to fix that without custom spindles.

Yes it is with all of the data and first hand experience posted by other track drivers. You on the other hand just posted what Hoosier told you, which was vague at best. Since it was designed for an 8 thats what you should run. This isn't rennlist, we do our own testing.

Cut the crap guys, youve both stated your side of the argument, no need to start insulting each other.

The Hoosier slick in question is still a radial, and it is not cantilevered like the DOT radial. 9.4" tread width, 10.0" section width. If you have any experience testing radials, you will already know that they will be fastest on a wheel roughly the same width as the casing, not tread. This does not change with sidewall stiffness. FWIW, the DOT is only slightly less stiff than the non DOT radial. I have mounted both on our 8's and 9's so I'm familiar with them.

I have spoken with Hoosier when developing both the 9" and 10" versions of the 6UL. This goes back before the 275 existed and I was talking to Jeff Speer about a 245/40. When they decided to do a 275 instead, he contacted me because he knew I was working on a 9" wheel. I think I was the first guy to post the 275 news on a forum. Anyway, I talked to an engineer there about the 275 and whether it needed an 10.5 or 11" wheel and he said that due to its cantilevered design, the 10.5 or 11 would not give it any more support than a 10" wheel. Thus, we made a 10" wheel.

The non DoT slick isn't cantilevered though so its needs a wider wheel relative to it's tread width.

If you have ever obtain any conclusive data under controlled conditions (same car/day/driver/track/weather/setup) that shows the 245/580R15 Hoosier is faster on a 9 than a 10" wheel, I'd like to see it.

Class they're designed for is both SCCA STU and Grand Am, both limited to 8" wheels for some cars. We supply wheels to a Grand Am team running a Mini that uses a version of this tire (Conti) on an 8" 6UL.

I don’t know much of anything about this car but it looks to be rolling on the 16”X11 or 12” tires I’m thinking of. Evedence I have seen is the stick is better than 275/35/15 A6 and yet it is a road racing compound that might be good for more than just one hot lap per session and maybe last a while.

https://www.miataturbo.net/attachmen...ine=1316041984

https://www.miataturbo.net/attachmen...ine=1316041984

https://www.miataturbo.net/attachmen...ine=1316041984

Bob

^ That car is tits

Xeleventy.

Who makes those wheels?

I think Keiser (Keizer?). Made to your specs.

They look like Kodiak wheels to me.

http://www.kodiakracingwheels.com/images/maloycsr.jpg

Ah, you're right. The Keizers don't have that distinctive little cutout on the spoke.

I guess with all the logic being thrown around by some all the extra frontal area will make my car slow when I build a car around these bad boys.

275/35/15 DOT Hoosier versus 23.5X11R16 Hoosier Radial slicks. Not sure yet if I will use 16X10 or 16X11 wheels. They acually look good mounted on 10's

https://www.miataturbo.net/attachmen...4&d=1317098216
https://www.miataturbo.net/attachmen...5&d=1317098216[/QUOTE]

Bob