bsztanko

15" or 16"?

Astroman

15"!!!! Good Lord!! I don't understand why this is so hard to believe...

Bela, Gary, trust me. Please.

Gary R.

I believe you Jack, wish one of them would post so Bela can calm down..

MPD47

Yes he will. It'll just take effort. You can stretch worse than that, not saying it's smart, just possible.

Gary R.

Hoosier says 8.5" wheel is good, can't imagine a 9" would create any major issues. That's .25" difference on each side.

Der ABT

If Bela and Gary say it cant be done....im gonna go with that and just think the tires i had were mislabeled or Woodman switched out my wheels

Gary you know the wheels i am running...only have those and a set of rains one day ill haev money for another set of wheels....definately 9s in the rear.

the 225/50 looked FUNKY definately a bit taller and not as wide(aka lay them next to a 275 and the difference is apparent....haha but it worked just fine, woodman boys didnt complain at all (actually stilll have the tires). you can tell it wasnt meant for a 9 in but as you say .25 each side is not much. no bead issues or anything

look at what bmw/vw/honda boys do with streatching tires.....

Gary R.

I never said it couldn't be done, I had no idea either way! Bela has mounted a ka-zillion tires.. So Evan, what difference did you see going from 225s to 275s and are you staying with 225s?

Comparison -

275/35 15 R6 - 20lb / 10.1" tread width / 23" rolling diameter - 9"-11" max wheel
225/45 15 R6 - 19lb / 8.8" tread width / 22.9" rolling diameter - 8.5" wheel max

Chris M.

225/45 on 15x9 BBS E75

Gary R.

Ever compare to a 275 or is that what you always ran Chris?

Der ABT

trade secrets

i liked both of them, i think each suits a track better.....give some here gain some there....275 was obviously more planted in the slow tight corners like 5-9 of summit just because it was wider.

i also think when yuo stretch out those 225s the numbers listed are distorted a bit but could be wrong(most likely am wrong)....tread width is tread width but??

i didnt drive my best as summit this year....watching the vids i left alot of time on the table...also that stuck throttle issues didnt help either....especially in the tire wall just glad it was cosmetic.

the 275 and 225/45 match up Very nicely front to back.....not sure how that set up would work square but i would think MAD OVERSTEER.....but some people like to drive that way.

Chris M.

I ran both the 275/35 and the 225/45 but never the 225/50. Actually, the first tire I put on my 15x9 wheels when I got them was the 225/45 for Road America 2010. I knew fitting the 275 was going to require some massaging which I didn't have time to do so I ordered the 225.

I also ran the 225 at CMP that year, then switched to the 275/35 for Road Atlanta 2011. The gearing is identical but I never noticed a change in grip with the 275. The 225 gets really nice and stretched on the 9" wheel. I specifically remember following Hupfer to the hot pits from the paddock at Mid Ohio one time and thinking how wide his rear tires looked and thinking, I need to upgrade to the 275 (this was when I was running 245/50 on 8" Fuchs). I went over to his car after the session and was surprised to see that they were 225s.

Before I sold my car, my next set of tires was going to be 225s all around. I figured if I can't feel a difference in grip I might as well go with less unsprung weight. If you are going to buy a set of tires for every weekend I could see using the 225/50s at some places (Putnam, Road Atlanta) and the 225/45 at others (the Glen, Road America) depending on gearing. Of course, you SC guys don't have to worry about that pesky rev limiter.

Gary R.

P245/50ZR15 R6 show an 8.5" wheel as max also....

Chris M.

I ran those on 8" Fuchs and once heard from a guy on Pelican that said he was running the 275/35 on 8" Fuchs as well.

analogmike

If they made a 245/40/15 that would be perfect... I love a 245 on a 9" rim.

I tried the 275 on 9" rears for the last race at Lime Rock this year. The gearing was perfect but the times were not really faster than the 245/45/16 I was running. I think the 275 should really go on 10" rims
for max performance. Also a taller tire theoretically has more grip (see RSR...).

I would have NEVER thought about running 225/45/15 all around but you have my interest now. I bet they would even fit on my BBS/Mahle rims which stick out too much for most tires (only 3mm offset). May stick some on for fun.

comatb

We have also run every combination of 15 inch 225/45 and 275/35's on 8 and 9 inch BRAID wheels. IMHO you must make suspension changes to actually maximize your wheel and tire choices. We see many drivers that think that just bolting on a different wheel/tire is going to magically be faster. It may be faster but not necessarily to the maximum potential. Data is the key to properly evaluate the effects of your choices for a particular track and realizing the trade-off on each section of that track.

We continue to search for the best set-up, just like you Gary Let us know when you find 'it'