NC autocross tires

[sammm]

What's the consensus of the tire size to use when running CS? The OEM wheel size is 17x7.

I'm thinking 215/45-R17 for tires?

[wrx74]

Tire availability is certainly best in 215/45/17 and 225/45/17 - or will be in March! Too bad the 215/40/17 isn't supported better.

[865]

I don't know if there is a consensus, but I've been running 225/45-R17.

[jrj512]

Buy sets of each, rent Mineral Wells, and see what's fastest.

[sammm]

Buy sets of each, rent Mineral Wells, and see what's fastest.

Have you met me?

I've been 'watching' these on Fleabay for awhile now...
http://www.ebay.com/itm/252669719825...%3AMEBIDX%3AIT

[cone-cerned]

I got a set of the 595RS-R, tread wear 140, to use on the track. After I got the tire pressure set close to right, I really like them, especially for the price. Mine are 205/50R15.

[sammm]

I forgot those are 140TW....not SCCA legal, are they?

[cone-cerned]

The 595RS-R is 140, the 595RS-RR is 200.

[sammm]

Thanks Doug.

[sammm]

Did some playing around with the FM gearing calculator....

[865]

^-- A little hard to read, but looks like 225/45R17 has the highest top speed in 2nd gear. I think that is why a lot of people use it for CS. 245 doesn't fit well on a 7 inch width rim.

Can you post the link to FM's calculator, Sammm? I haven't seen that one before.

[sammm]

You are correct about the 225....here's the link.

https://www.flyinmiata.com/tech/gearing.php

[865]

Thanks!

[Robert]

The 595RS-R is 140, the 595RS-RR is 200.

I heard that the early made RR have 140 stamped, and the later ones have 200 stamped on them. If you get them make sure you get the 200

[CosmosMpower]

Go figure the stickier more aggressive tire has a higher treadwear so it can run in SCCA.