East Tennessee Region SCCA

There have been circumstances where nationally competitive people have chosen the R compound for autocross....generally for FWD in hot weather with fast turn around, like a Pro. I think Pilson/Trey ran them in the Subie in HS. Several HS folks used to run them. The late Jim Feinberg won on them.

90civichb wrote:Isn't there a pretty large difference between an R7 and a 100tw tire? Also not sure if any of the cars are xp legal really. I would need to trim back aero, add weight, buy back interior pieces....I would probably just stick to STM and do what Lucas did and DFQ myself if I decide to buy some track type tires for next years attempt at some HPDE.

Agree 100%. I have very little desire to buy new 200tw tires at this point, and no desire to run in a class with 3 people on a7s when I have "street slicks."

I've got no problem with an "unofficial" STM sub-class, whether the times count or not. I'd drive to events on the RC1s.

It's Street Tire Modified. Not Track Tire Modified.

Wouldn't you want to save your 100tw track tires for track use? Granted, the 200tw is just BS lip service.

We had planed for STM to have a period of 140tw for folks to burn up their old tires and to let the ubber competitive folks sort out the 200tw tires so the STM folks could make a wise purchase with known info. Any track day, R or A comp tires are eligible to run XP or whatever open prepared or mod class the car would legally run in.

You can over tire a car. The compound never gets to temp thus no grip, you just slide.

You can under tire a car. You cook, blister, chunk away a softer compound like the A's. If you can't run a larger tire to absorb the heat, going to a slightly harder compound, the R's, the tire will survive. A's and R's have about the same grip at the same temp. A's will fire quicker, and then overheat quicker.

lcoleman wrote: Agree 100%. I have very little desire to buy new 200tw tires at this point, and no desire to run in a class with 3 people on a7s when I have "street slicks."

I've got no problem with an "unofficial" STM sub-class, whether the times count or not. I'd drive to events on the RC1s.

So you have outrawed the 3 folks in XP when you were on 140tw tires, and you want to run in another unofficial class with maybe 3 people now that you have softer tires and will be faster?

I'm missing something here.

I understand not wanting to buy tires for the occasional autoX since you will be focusing on track days.

Jim typically outraws all of us, even when we're on 200tw. For me, it's mostly about running with my friends in STM.

Logistically, I think it's justifiable because the 100tw stuff is going to be slower on all but the hottest, back-to-back runs at Bristol, and even then I'd say it would be pretty close. I get why it hurts the outward perception of the class, though. I will probably continue to run STM whether or not I have to dsq myself each time.

I will just run Emod on the wrong tires till I can find some wide 200tw tires.

thewelder wrote:I will just run Emod on the wrong tires till I can find some wide 200tw tires.

Here ya go 245/40/15 200TW:
http://shop.maxxis.com/c/automotive_vic ... ted_post=1

Also, talk of a 275/35/15 200TW VR-1 :
http://www.miataturbo.net/wheels-tires- ... 200-91088/

thewelder wrote:I will just run Emod on the wrong tires till I can find some wide 200tw tires.

I would heed Dave's advice. I got to drive his locost, and it was a HANDFUL on Hoosiers. Screw a 200 tw on that car!

I can't buy wheels right now. But I may get those maxxis. I hadn't found those in my searching. Thanks.

I sent maxxis an email about them and asked about a release date. That would mean 245 front and 275 rear and I can take out 300lbs of weight. Look out STM. I am coming

Would a really light car like a Locost heat up tires like that as well? I don't think a 15x10/245 VR1 combo would really be as grippy or get up to temp as fast a 15x9/225 Rival S.

Chuck629 wrote:Would a really light car like a Locost heat up tires like that as well? I don't think a 15x10/245 VR1 combo would really be as grippy or get up to temp as fast a 15x9/225 Rival S.

If the compound is the same, size is king with auto-x. Unfortunately there's a compound difference between Rival-S and VR-1.

No one that I know of has ran on the new rival s compound as of yet, so that new compound could make the stones the 2nd best tire in smaller sizes.

The 245 maxxis was about half a second slower than the 225 rivalS. But I will be street driving this car more than I am racing it. If the 275 comes out soon I will run them in STM just for fun.

I ran the 225 RivalS this season. It's a good tire and has good street manners as well. On a light car like mine they heat up pretty quickly. They also communicate well when they are on the limit. They wear quick. I ran them at about 23psi squared and that seemed to be a pretty good sweet spot. Car comes in at 1800lbs. If you plan to put a decent amount of street miles on the car I would go for the Maxxis. If you want to seriously compete in STM I would go for the Rivals or Stones.