Hi, what do you recomend for R compounds for my moded 2004 Sti? I am planning to take it to Auto Cross and track days.
Are you trying to stay in a certain class in auto-X, or are you just wanting some tires to beat on? You have 17" wheels still, right?
I am driving the SM class and looking to have fun and be as competitive as possible. I just thought it would be a good investment to have an extra set for AutoX and track days. I have the srock Bridgestone Potenza - that's 17" - right?
If you have never ran on R compounds Road Atlanta is not the place to start. They are very very diffrent than street tires, the break away is not nearly as composed and you need to have extremely fast hands, they don't usally make noise before they go, so there isn't really any warning. Matt
You'll want to 'test' the limits before you go on track... i.e. skidpad I can get you some Michelin Slicks for fairly cheap, but they would only be able to be used for track days. Unfortunately, I am fresh out of the Hoosiers
Mostly 18"s, but there may be a few 17"s mixed in. I think that there are a few of the 17" Hoosier slicks (not R6)
Most track tires won't get hot enough for autox competition, Hoosier A6 and Kumho V710s are the pretty much the only R compounds you see on "street" cars at SCCA competition.
unless you're cheap and buy used RA1's. They aren't THAT bad. On a mildly cool day they might start to heat up a little by your last 1 or 2 runs. Or at least thats what I've heard.
The best compromise would be V710's. 275/40/17's on an 8 inch wide wheel would be good. You will have to either raise your car up, or do some slight body work (fender rolling/pulling) to prevent rub. Otherwise, find a 245/40/17...no V710 in that size...but the Ecsta 700 comes in that size and does fine on autox, but I do not know how well it will hold on on your STi around a road course. Thats where the Toyo RA1 and Hooiser R6 are best. The Hooiser being the best.
Go with the R comps, not the A comps. If this is your first time on race tires, you will need them to last as long as possible. The A comps are just for serious autox'ers who already know how to drive on them. They burn up really fast espeically in the Atl. heat. A set of R comps will last you more than a year, while the A comps will last you only a year. The R comps are cheapier and you can find them used more frequently with a lot of tread left on them. If you decide you want to track your car later also, the R comps will be better suited to handle the longer race times. Thats my opinion... Good luck.
What do you have against the 245/45-17 v710? It is the same height as the 275/40-17. Here is a comparison pic of 245 vs 275 v710 on a 17x8 wheel http://www.tastybeef.com/sti/pink-275s.jpg IMO, for track days, I would just stick to street tires, and get some nice v710s for autoX. I wish that we stuck to this, as we killed 2 sets of RA1s on track days last year. Also, for the RA1s, they sucked for AutoX at full tread. I compared them back to back to my street tires at the time (Yoko Neova AD07s), and the Neovas felt much better I would buy Neovas for running in an ST class way before I would get another set of RA1s for AutoX. -- Brian
I think that a 245/40 V710 would be better than the 245/45/17. I've run 245/45 in STU vs 245/40 and the 40 is way better. While it IS a street tire vs race tire sizing comparison, I have not been wrong in the past about it.