Quickest AX tire for 13" wide rims?

[ted]

I'll be entering an AX with only a 50 second lap length and a required 5 minute cool down between laps.
You only get 3 laps too.

My 911 has 10.5" wide front rims and 13" wide rear rims, either 17" or 18" diameters.
What tire do the AX pros use for this application?

So far a Hoosier A series is said to be better than my 710s, opinions?
Any soft slicks that would be quicker than the DOT tires?

Photo of car, 2400lbs, 3.6, trick suspension and gearing.

[scca_ita]

Mike, Check with Tom Tweed. He has some nice 16x10s 12s that would fit under your fenders nicely. Use Hoosier slicks.

I think with your cars weight you would be hard pressed to find a tire for a 13 that you could scrub heat into to be effective. Not to mention the cost of the tires would be more alone than what Tom's setup could be.

[J P Stein]

Humm, the Parade is in SD this year, eh.

You'll be in Mod 6 if memory serves.
R35 Hoosier slicks are the weapon of choice there. On concrete, slicks are good for 2 seconds or so, considerably less on asphalt...maybe .5 sec.
You don't wanna show up with a knife at that gunfight

[70rsr]

Hoosier A'6s are the only choice for your wheel size. Try to give them one or two good scrubs at an event before the big event you are entering. There are no slicks in the size you need that will heat up as quickly.

[ted]

Good advice, thank you guys.

I'm trying to decide between the narrower R35 or the wider A6.
Have not figured out yet what width I'd have to run if I did have R35 slicks.

So whats the best set up?

A6 on a 13 wide rear rim?
Do you think the 10.5 wide A6 fronts can warm up quick enough?
Never ran an A6 how are they after one lap and sitting 5 minutes before the next lap?
Good to go?
I will be in pre grid for an hour so no pre warming allowed.

Would the largest R35s be noticeably quicker than the 13 wide A6?

I read on another forum that on a minute long course the R35 slick was 2 sec quicker on concrete and only .5 second quicker on asphalt.
Is that correct?

question #2
I have turbo brakes with pagid orange pads which take too long to heat up at the AX.
What pads should I run at the AX?

[Cookie Porsche]

Ted,

Don't know your rules but for extreme initial grip you can 'paint' the tires with Tire Grip - a product used in drag racing and if tire life is no object. You must paint the tires 24 hours before the event and leave them off the ground. Grip will be instant.

For pads try Pagid blue - and even better run a few looong hard brake runs before lining up. Even if you sit for 5 minutes the brakes will be warmish and the first stop will be significantly easier to modulate than with ice cold discs/pads.

Most importantly do NOT lock up brakes in events like these - the flatspot will be the end of any TT.

Tom

[ted]

Originally posted by Cookie Porsche
Ted,
Don't know your rules but for extreme initial grip you can 'paint' the tires with Tire Grip - a product used in drag racing and if tire life is no object. You must paint the tires 24 hours before the event and leave them off the ground. Grip will be instant.
Tom

You reminded me I did paint a set of old tires 5 years ago and the grip was incredible for about 10 minutes....

Maybe a 3rd option just paint some decent 710s?
It's only 3 laps.
The blues sound good, but no warm up time allowed.

[Cookie Porsche]

Originally posted by ted

The blues sound good, but no warm up time allowed.

Also no warm up here, but even a 'detour' to make a U-turn before lining up could get you a few 60-0. All is fair in love and war!

Tom

[ttweed]

Mike-

I think the ideal AX setup for your car would be to run the new Hoosier radial slicks in FA sizes with the R25B compound. Nothing else would be faster on your car at Qualcomm. The trouble is, you would have to buy new 15" rims that fit over your turbo brakes to run them, and the tires alone will be ~$1300 for a set, I think. How much are you willing to spend to run 3 laps at the Parade?

If you run the bias ply slicks, you are going to have to set your car up with less camber, as they don't like the amount of negative you run for your radial tires, and you still need new rims, as they don't come in 17" and 18" sizes. Even the 16" GT1/GT2 sizes don't come in the softest R25A compound, so you have to settle for R35. I would stick with the V710 or A6 choices. It's a tossup which one is better. If you already have the V710s, I would just go with those and hope to drive better than Greg Fordahl and Erik Kinninger.

TT
ps- I just run cheap street pads with my turbo brakes for autox, since fade isn't an issue and they work better when cold.

[air-cool-me]

can you use those heat blankets or anyhting to keep the tires as warm as you can in between runs?

[ted]

Originally posted by ttweed
Mike- I would stick with the V710 or A6 choices and hope to drive better than Greg Fordahl and Erik Kinninger.

TT
ps- I just run cheap street pads with my turbo brakes for autox, since fade isn't an issue and they work better when cold.

Thanks guys for helping me figure out my options.
All very helpful ideas.

Due to the settings on my raised front struts I only have ball joint to rim clearance for 17" and larger diameter rims.

After considering tire sizes and compatible rims diameters it appears I'm limited to the A6 or 710 tires for now.
Is there really no super soft radial slick in my size?

Hope? TT is that what you used on me during timed runs a few years ago in Pahrump?

[ttweed]

Originally posted by ted
Due to the settings on my raised front struts I only have ball joint to rim clearance for 17" and larger diameter rims.

Oh-oh. Then 15" rims are out for sure. Have you tried 16", too? Is there really interference with anything smaller than 17"? You must have raised the spindles a bunch.

Is there really no super soft radial slick in my size?

You can try the Goodyears, but be ready for the "sticker shock"--price list is here. The trouble is they don't make anything for your 10.5 fronts in the softest compounds (R160 or R165). You can check with Michelin, Dunlop and Yokohama, but I think most of the GT slicks are going to be a harder compound than you want for autox, since they are made for road racing. Check with Kary Clements, he has been using 17-18" slicks on his 993 for quite awhile, but he doesn't autox any more. He may know what is available, though, since he has started his little Group 9 Motorsports gig. At $500+/tire, I have never even considered them.

TT is that what you used on me during timed runs a few years ago in Pahrump?

No, I used the Goodyear bias ply slicks on 15" and 16" rims. I still have a set of Duralite alloys in 10" and 11" x 16" w/ RSR offsets, if you want to try to fit the fronts on your car and check clearance on the ball joint. I was thinking about selling them anyway, and the fronts are bare right now if you want to borrow them. I have a set of Hoosier slicks for them in 20x10-16 and 23.5x11.5-16 also, but they're the R45 road racing compound.

Those aren't the sizes I was running that day at Spring Mountain-- I had 10" Goodyear slicks in 410 compound on the rear on the 11x16" Duralites, and 9" cantilevers in the front on 7x15" rims, but they were my "secret weapon" that day, as they are so short, they lowered my gearing and CG for that short, twisty track, and it was warm enough to get some heat in them in a couple of laps. I only put them on for timed runs, and I went a LOT faster than in practice, which resulted in some "sandbagging" grumbling by people who had been passing me all weekend while I was on the Victoracers.

TT

[ted]

Thanks again Tom, I would like to test fit one of your front rims.
Sent you a PM.

[gulf911]

Ted?? Ted??


Hey Mr G.!

You might consider the Raybestos pads as my experience has been they heat up quickly and require much less pedal pressure for the same stopping power. A word of caution, drive with them a bit to get used to the grip or you will flat spot. The other option would be the porterfield Race pad. These work great as well.

Good luck at the parade!