Cal Club Autocross Forums

I'm currently running a 195 Re-01 on my 15 x 7 wheels but was considering going wider.
What have you guys found to work best while still fitting properly on the rim?
Would going to a 225 be too much for the 7 incher?
Will the tire bulge too much at the side walls?
If so would I get better traction using a narrower tire like a 195 that is probably more along what is normal for such a rim?
I've heard, that I could probably go as wide as a 245 on these rims if wanted to?

Just figured you guys would be the best to ask vs most other sites I visit.

Thanks.

In you particular situation, I would suggest 195/50-15 Toyo R1R. Most of the ST and STS competitors are using 195/50-15s on 7.5" wheels.

And there is actually a drop off in grip with the 205 Toyo R1R

... but I would vote for the Hankook RS3 in 225/45/15: http://www.tirerack.com/tires/tires.jsp ... &tab=Sizes" onclick="window.open(this.href);return false;

Please buy from The Tire Rack and use the link at the bottom of the page, as we get a kick back

Sebastian Rios wrote:In you particular situation, I would suggest 195/50-15 Toyo R1R. Most of the ST and STS competitors are using 195/50-15s on 7.5" wheels.

Agreed.

Mako to wrote:
Please buy from The Tire Rack and use the link at the bottom of the page, as we get a kick back

Bummer is that Tire Rack don't sell Toyo's for some reason...?

& I was eyeing the Toyo R1r's actually.
& you saying the Toyo's drop off at 225 & yet the Hankooks don't?

No, that's not what I said. The Hankooks will last you longer, especially in the summer

My vote is for the 195 Toyo which will last plenty long. Those things are some sort of magic!

So is there a down side to going wider than 195?
Like 225 or more?

The National Championship winning STS Miata was on 195 Toyos.

275/35/15 Hoosier A6 works on a 7" wheel. Oh, ST, never mind..

Cam Correa wrote:So is there a down side to going wider than 195?
Like 225 or more?

The downside is that you go SLOWER. Some complicated explanations... but ultimately I see it as a nobody really knows. The closest to the 195 R1R is probably the 225 Hankook RS-3 which is a very good long lasting tire though your first run is a throwaway. I'm not sure what the Bridgestone guys run, probably a 205-50-15. All three diameters are a tiny bit different which can be a course dependent thing. But you're lucky to run in a region with a number of the fastest ST/STS guys in the country. We know what is fastest, what is close, and what the trade-offs are. And most of us have tested the heck out of the various brands, sizes, and combinations.

Copy who is fast until you get to the point that you can lead the pack and let others copy you.

Talk to Jon Lugod and Mike Heinitz.

Steve Ekstrand wrote:

Cam Correa wrote:So is there a down side to going wider than 195?
Like 225 or more?

The downside is that you go SLOWER. Some complicated explanations... but ultimately I see it as a nobody really knows. The closest to the 195 R1R is probably the 225 Hankook RS-3 which is a very good long lasting tire though your first run is a throwaway. I'm not sure what the Bridgestone guys run, probably a 205-50-15. All three diameters are a tiny bit different which can be a course dependent thing. But you're lucky to run in a region with a number of the fastest ST/STS guys in the country. We know what is fastest, what is close, and what the trade-offs are. And most of us have tested the heck out of the various brands, sizes, and combinations.

Copy who is fast until you get to the point that you can lead the pack and let others copy you.

Grassroots motorsports did a number of test with a Miata and found larger was indeed slower. I will see if I can find the article.

Arthur Grant wrote:

Steve Ekstrand wrote:

Cam Correa wrote:So is there a down side to going wider than 195?
Like 225 or more?

The downside is that you go SLOWER. Some complicated explanations... but ultimately I see it as a nobody really knows. The closest to the 195 R1R is probably the 225 Hankook RS-3 which is a very good long lasting tire though your first run is a throwaway. I'm not sure what the Bridgestone guys run, probably a 205-50-15. All three diameters are a tiny bit different which can be a course dependent thing. But you're lucky to run in a region with a number of the fastest ST/STS guys in the country. We know what is fastest, what is close, and what the trade-offs are. And most of us have tested the heck out of the various brands, sizes, and combinations.

Copy who is fast until you get to the point that you can lead the pack and let others copy you.

Grassroots motorsports did a number of test with a Miata and found larger was indeed slower. I will see if I can find the article.

Very interesting thank you very much..

Kurt Ra wrote:Talk to Jon Lugod and Mike Heinitz.

What am I chopped liver?

I have driven on all the tires and sizes mentioned, in some cases mounted on 7" and 7.5" wheels.

I believe that given the facts Cam has presented, the fastest tire in an autocross setting will be the Toyo R1R 195/50-15.

Sebastian Rios wrote:

Kurt Ra wrote:Talk to Jon Lugod and Mike Heinitz.

What am I chopped liver?

Don't know about your tire knowledge, but you're definitely the goto guy for how to drive the motor home...................

[quote="Sebastian Rios"]
What am I chopped liver?

Better question for us skirted ST types is what tire does Shauna like?

When I said I wanted to run less then 225 on track, I got laughed at

Interesting, AX'ers have gone away from more rubber is better.

Mako to wrote: Interesting, AX'ers have gone away from more rubber is better.

We haven't. It's just that the 195 Toyo > *

Street tires just simply need as much sidewall support as it can. So a 195 on a 7.5 is ideal for us lighter cars on those toyos. Each tire is different and I believe sidewall is key. Stuffing a 225 on a 7 is doable, you'll just need to run higher tire pressures to keep the tire happy. For autocross I think this is important since we transition a lot more than any road course can offer. What works for autocross doesn't necessarily work for track.

Sebastian Rios wrote:

Kurt Ra wrote:Talk to Jon Lugod and Mike Heinitz.

What am I chopped liver?

Not chopped liver, but possibly ground beef. I mentioned those two peeps because Lugod has given me excellent advice on tires in the past, and Mike has run an STS Miata for years, so I'm sure he knows a ton.