13 and 14" tire availability?

[jmcfarland]

I know, I know... everyone is running 15's and up. But what about older cars that were designed with 13" tires? Are there smaller sizes available from anyone with TW200? Going big isn't always better on suspension / hubs/ bearing on cars with 13" designs.

 

Just shaking up the bees nest a little.

[collinskl1]

nope, nobody is making modern small diameter tires

[enginerd]

48 minutes ago, jmcfarland said:

I know, I know... everyone is running 15's and up. But what about older cars that were designed with 13" tires? Are there smaller sizes available from anyone with TW200? Going big isn't always better on suspension / hubs/ bearing on cars with 13" designs.

 

Just shaking up the bees nest a little.

Any car with factory 13” wheels will have such a low VPI that you can fix those issues and have several hundred points to spare.

Go 15”

Or take it as a warning sign that you think the components are too weak to handle 15” wheels... in addition to hubs / suspension, the engine is certainly too weak and will need to be swapped along with trans and diff. Axles as well? Sounds like a mountain of work. 

Edited January 26, 2021 by enginerd

[jmcfarland]

31 minutes ago, enginerd said:

Any car with factory 13” wheels will have such a low VPI that you can fix those issues and have several hundred points to spare.

Go 15”

Or take it as a warning sign that you think the components are too weak to handle 15” wheels... in addition to hubs / suspension, the engine is certainly too weak and will need to be swapped along with trans and diff. Axles as well? Sounds like a mountain of work. 

Gen 1 RX7 - Prepping for 15's. They just came with 13's originally and all the geometry is designed for it. Just asking...

Edited January 26, 2021 by jmcfarland

[mhr650]

Gen1 RX7 you definitely want 15-inch tires, this is my car with 245-15’s. Don’t worry about the diameter, a stock 185-70 13 tire is 23.2 inches in diameter, a 245-40 15 is 22.7. You also need bigger wheels so you can get rid of the awful first gen brakes, the standard setup has way too much rear bias and is easy to loop under the brakes.

 

Nobody races a first gen RX7 with 13-inch wheels unless the rules require it, like some historic classes.

 

Edited January 26, 2021 by mhr650

[Timothy G. Elliott]

Federal makes some great 14 inch we are running on my GTI, they stick well and hold up well, they seem to be about as good as the Early 90's Bridgestone RE-71's I use to run in ITB on my Scirroco. The held up well with no complaints from my driver's at Road America this last fall and I agree that larger tires are not always better. They are very reasonable also! $215.00 for a set of 4 shipped to my house! 

[wvumtnbkr]

If you want to be competitive, go 15s.

[DEE DEE]

6 hours ago, jmcfarland said:

I know, I know... everyone is running 15's and up. But what about older cars that were designed with 13" tires? Are there smaller sizes available from anyone with TW200? Going big isn't always better on suspension / hubs/ bearing on cars with 13" designs.

 

Just shaking up the bees nest a little.

You want that 13" in a cantilever tire ?  I have some.

[craig71188]

Might want to call Brian Hoover at Auto Body Specialists in Columbus, OH.  He was running a pretty quick first Gen RX-7 in Champ.  He may have some good input for you.  (Pretty sure it was on 15's as well.)

[mhr650]

13 hours ago, DEE DEE said:

You want that 13" in a cantilever tire ?  I have some.

 

I saw some of those once, from IT racing back in the day when you had to run stock wheel sizes. I think it was a 225 Hoosier on a 13 X 5 or 6 wheel, strangest thing you have ever seen

[Timothy G. Elliott]

Sounds like Formula Ford tires from the old days. Had alot of them to choose from.