kabel_Boxster

I typically run 33-34 psi in front and 37-38 psi in the rear on my PS2's for autox, that works for me. Your results may vary

Stealth 993

Harry, no, I have not let them drive my car, let leave it at they are less then interested in stock classes. I have had other people drive it & I was with in their time. I also have a national SCCA guy in my class that I battle back & forth with.

This was a "how do I get better post" it's a what a great stock tire post. I'm not going to compete nationally, or with the SCCA, I just want to be a little faster then I am now & need a little more grip. My current tires were $350 for a set of 4, fast they are NOT!

The EVO school is news to me, no one locally has talked about it at all. I see they are going to Packwood in July, I might check it out, but I think the PCA is there the week before the SCCA event.

I have no doubts they will work, but they will not be as fast as some of the others, but I got my PS2's on close out, & they were really cheap!!!

Yea, they are 4lbs front & 6lbs rear each lighter then the AD07's. I run nitrogen @ factory specs 36/44 then go from there. Usually I run 42 rear & 34 front.

sjfehr

One of the local clubs here is having an EVO school this coming fall that I am NOT going to miss! They also have a cone clinic coming up in a month that's just like the evo school, only taught by the local champs, which is just fine for me and literally 1/10 of the cost I highly recommend it to anyone and everyone! The seat time alone is worth it.

targa86

I run B-stock in SCCA but don't run Stock class in PCA so I'm not sure how much latitude you have in tire sizes.

You are correct that the best tires don't seem to be available in your sizes. I would suggest that you consider the Dunlop's with a change to 215/45/17 in the front. Get a second opinion on this of course, but it seems to me that this should be OK for your rim width and fender clearance. If that change works and is legal you can be certain you aren't going to be out-tired.

The Boxster's other advantage over your 993 is its rotation speed. With its high polar moment it simply takes a little more pavement to get a 911 turned in. If you want to win bad enough and have quick reflexes you can compensate with a little bit of positive toe up front. It only takes a little to make a car absolutely twitchy, which can be good for autocross. Too much can make the car unsafe for street or track use, so be careful. I agree with the previous post that rear toe should be close to 0. I would leave it a little negative since positive toe in the rear bites you hard and fast.

There is an awful lot of very good autocross advice in this thread, take it all in and you will get faster.

Stealth 993

I can't change anything, but tires, & can't plus size. It's a "Showroom Stock". Even 140 tread wear tires are pushing it.

It's my daily driver, so I need to keep the alignment civil. My C4S has 0 toe in the rear & just a tad toe out in the front, a little over 1/2 deg of camber all round. Not tire friendly, but it goes where I point it. Most likely, I'm going to try 0 toe f/r then dial in just a bit of camber, then re-corner balance.

calicoupe

^Im in your same predicament. I run in NS/S class with my 996 and I am chasing Cayman S. The fastest driver we have runs in my class is on Dunlop Direzza Sport Z1 Star Spec.

I have asked several SCCA national drivers that we have in our autx in Orange County and they said if they ever ran in stock class this would be tire, Dunlop Direzza Sport Z1 Star Spec if sponsorship was irrelevant.

In terms of alignment, max camber in front and I am running a bit toe out front and 0 in the rear. Rear camber is 1.3 degrees.

Tires - if i recall 245 front and rear 275. With stock suspension I must hit the breaks (which I dont like to do) a bit to create rotation on my car so I like a wide as possible front tire.

Last week, I got rid of falken rt615 and bought a set of these and will try them this coming Sunday. We shall see.

It's a great challenge and it just makes your work a bit harder! cheers

sjfehr

I did discover one thing about the Z1 Star Specs, and that's that they get HOT and you've got to treat them differently than "normal" street tires! You need to bleed them like r-comps and maintain hot pressure between runs, or the grip falls off fast. I never had to worry about that with my old tires... First time I raced them in the dry, I lost 2 seconds between my first run and my last runs due to this, and was hitting cones all over the place from the surprise understeer of the rear end losing grip early. Next race, it was an even hotter day, but I had it figured out, maintained pressure, maintained grip, and placed 1st in street tire class.

I do have some very weird tire wear in the front; like the compound in the middle of the tire is softer than the compound on the edge, and is wearing faster, but not evenly- it's like a step when I look at the tire. The inside "corner" of the tread on the sidewall almost looks like it's melting after I get through with my runs. But only on the front, not the rear tires:
/---- ___ ___ ___ ----\

I'm running 39/39psi hot to race, btw. And 28/34 cold for street. At least per the gauge on my pump- there's a 15psi difference depending on which of 4 gauges I've used.

Jim Michaels

Stealth: The June issue of Grassroots Motorsports reports findings from their recent SCCA street tire comparison test. The six tires they tested on their AX course had the following average times/best times.

1. Kumho ECSTA XS = 34.170/34.030
2. Bridgestone RE-11 = 34.266/34.238
3. Bridgestone RE-01R = 34.478/34.430
4. Toyo Proxes R1R = 34.522/34.452
5. Dunlop Z1 Star Spec = 35.209/35.061
6. Falken Azenis RT-615 = 35.302/35.125

Tires were shaved to 3/32" and tested on the Honda Civic of Andy Hollis. See the report for other details that may be helpful.

calicoupe

^ great data and info

Wilder

Stealth: There is no "best" tire. "Best" is dependent upon surface, course, car setup, weather and driver style. That said, I recently researched AX tires (in the market too) including polling guys that run at SCCA nationals and from the info I gathered, the Dunlops are an excellent choice (and what I'm buying) for heavier cars in NW weather for the following reasons:

1 - They heat up quickly. You need that in the NW.
2 - One of the best wet performance tires. Again, you need that here.
3 - Very stiff sidewalls = great performance specifically on heavy cars.
4 - Extremely sticky and long lasting compound.
5 - Very affordable for what you get.

Toyo R1R may give marginally better performance if at all but they won't last as long and they cost more.

RE01 and RE11s are great for lighter cars but heavier cars don't do well on them (softer sidewalls) and they cost much more than the Dunlops. I'm sure if you contact Andy Hollis, he'll tell you not to buy the Bstones for a 993 due to weight. I hope you haven't bought them yet.

There are other very good choices out there but they won't be as good a choice as the Dunlops. The Kumho XS are getting rave reviews (as verified by the SCCA test numbers above) BUT they don't perform well in the wet so a no go for the NW. The new Hankook RS3s look great on paper but they are so new that you're making a blind bet. The Yokos AD08s get great reviews but like the Toyos, they may not offer significant performance gains over the Dunlops to justify the expense. Falkens are great...I've ran them in two cars but they are a "has been" tire and there are much better choices today.

Good luck with your choice.

Jonasz

hello
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Edited by John D. - who added:

Good-Bye!