Bias ply tires SUCK to autocross on BTW. We tried some of the american racer 13x10s (IIRC) and when they finally got hot enough, they were about as sticky as the a6s, so cheap... but so hard to drive, totally different and inconsistent and just a pita. I'm sure for track days it wouldn't be nearly as bad tho.

 

Which american racers? I hear they make some tires that are actually decent to auto-x BUT you have to ask them for them since most of the tires they sell are kind of spec or circle track tires. IMO if I can run a non-DOT tire, I'm going to run Avons.

 

This.

We're NASA racers and their classing structures reward soft compound in widths that are stamped narrow. Thus, everything of importance is won on the narrowest A6 that fits your car. The biggie for the 245/40/15 will be ST2 as that's the break point for getting dinged on lbs/hp ratio. Several guys around the country are planning a be-winged, F/I Miata on 15x10 6UL's and those made-for--ST2 A6's. I can see an ST2 Miata getting disturbingly close to GT3 cup car records set up thusly.

 

So you had a bad experience with a bias tire and therefore they all suck?

 

So some random roundy round tire didnt work for non-roundy usage? Color me shocked. Absolutely shocked. Bias ply are fine for auto-x, just try to get the right compound and tire for the job. Those Goodyear Formula Atlantic were pretty dang good on my car last year, less so this year as I need more gearing and rubber for the increase in power.

FYI-
American Racer has realized they don't make a tire suitable for auto-x use. At least one Modified guy is working with them to see what might work. Many of the autox world would love to not have to buy British TYRE crack and the Purple brand of crack just doesn't seem to keep up (although rumor has it those are getting an update soon). Of course this is thread drift since none of the discussed tires will be DOTs.

 

Things are looking great for my car in ST2 this year with the 245 A6's on 10's. Now if the driver can get up to speed is a whole other question. I feel like I got the right car for the class and look forward to a fun year. My home track in Sonoma where I feel the lightweight design of my car works best.