frayed

Hoosiers stick like mad no matter what, and while I'm sure Davepk and Krazik are accomplished drivers, I'm going from the experience of race teams that make their living driving fast and building race cars for professional drivers. Folks who put food on the table as a function of fast lap times.

Case in point. The bad boys from bimmerworld in ITS cars race both the Speedvision World Challenge, BMW SCCA Stock, Prepared, and Mod classes, as well as SCCA ITS classes. They've found faster laptimes migrating to 225's (max class width for certain classes in which they compete) on 8.5" rims. That's a wide rim for 225's. They noted too much sidewall flex sacrificing turn-in, precision, and feedback with narrower rims.

Two fastest racers in H Stock, run 8.5" and 9" rims. . . about the widest rims you can fit on an E36 chassis, both running 245 Hoosiers or 255 Toyos. Both note improved lap times. One of the two is a yuckety yuck at Tire Rack and hard core club racer (just call and ask Jim from Tire Rack about him, his name is Wayne), and the other is a friend of mine.

I've had both 8" and 8.5" rims on the track in my E36 M3. The 8.5" rim is a hot setup, yielding improved predictability, faster more accurate turn-in, and generally speaking a better handling car on a road course. I now wish I opted for 9" rims, which would require a bit of fender rolling to fit on my E36.

As to unsprung weight/rotating weight of a wider rim, it's negligable. An SSR comp in a 17 x 8 vs. a 17 x 9 is 5 lbs at best.

Finally, I spoke with the head engineer at Kumho USA. His name is Rick Brennan. He suggested going as wide as possible within a given range, noting impoved grip and precise turn in.

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While most of my experience is with my M3, the same physics apply to an S2k on a road course.

davepk

I certainly agree that if you have a choice you should go with wider rims for the reasons all of you mention. I to have had similar experience with wider and narrower rims. However, Chico S2000 was looking for a recommendation between to distinct setups both of wich use the oem rims. In his case there is no doubt in my mind that the 225 275 setup will outperform the 205 245 setup while also providing him with the reduced push he is looking for.

cthree

I agree with dave. Hoosier 225/275 combo is the best DOT-R solution on stock rims. That was the question, that is the answer. I can't touch them with 225/245 RA1s nor can anyone else I know.

If you care to test your theories come out to Buttonwillow in Sept with SpeedVentures and Rylan and his Hoosiers will spank you personally.

jzr

One person in one car against another in a different car is hardly a good comparison. I was quicker than Rylan (and his Hoosiers) in my bone stock car on 225/245 A032Rs at Spring Mountain, but that's doesn't make my tires better.

I vote 225/245 with a bigger front swaybar over 225/275 and stock swaybars. If you're in the financial position to afford brand new Hoosiers, you can afford to get yourself a decent front swaybar. It'll make your autocross/track driving much more enjoyable, without negatively impacting street performance.

I'll miss BWillow due to a little road trip to Kansas the preceding week. Wonder how many S2000s on the grid in Topeka will be wearing 275s?

Have fun out there guys!

Jim@tirerack

ENE,

The Pilot Sport Cup is designed and intended to drive on the street to the track. I would like to see somebody get 2 track days, 4 auto crosses and 4000 street miles on any of these other tires.
The tire was designed from the Michelin endurance racing tires. The Sport Cup does not like high pressures or heat and they work much better with little negative camber. They are different than the other tires and will nto perform as well if these criteria are not met.
We do have a spec sheet on how to run the Cup tires.
If I can help let me know.

Jim 800-428-8355-364

Jim@tirerack

JZR,

The Pilot Sport cup likes low air pressure and low heat and little negative camber to work at its best. For a tire that is DOT approved I haven't seen anything better. If you were by chance testing a full tread Pilot and a Hoosier remember the Hoosier is 3/32 and the Pilot is 6/32 tread depth. Also the Pilot you can drive on the street and the Hoosier is not recommended to be driven on the street. Even though the Pilot does cost a little more we have been seeing 3 to 4 times as long of tread life.

Jim

Jim

jzr

Jim,
I agree the Pilot is a fantastic tire. I also agree with the 3 to 4 times the tread life - in fact, I would argue that with the street miles, it's really a lot more than that. I might even say that technologically they're a step ahead of any other tire I've used. But there is that smidge of compromise given towards longevity and streetability. Hoosiers, with their uncompromised compounds and contruction, are able to retain the performance edge even with their slightly lower tech.

If I manage to have enough $$ to compete in the Open Track Challenge next year, I will do my best to run the PSCs. They're clearly faster than the Yokohama A032R, and still have a high enough treadwear rating to be eligible for the OTC's "Touring" classes (unlike the similar-performing Victoracer and RA1). They survived a 115mph off at Willow Springs and came out shining (which is more than I can say for my fender liner). Unless it gets banned, I think it'll be the tire of choice at OTC next year. Looking to sponsor someone?

That spec sheet sounds like it'd be very interesting. Any chance you could post it here?

A stock S2000 won't be able to attain camber readings that are really out of range for what these tires like. @ -2.5* in the rear, wear is pretty much perfect. @ -1.5 in the front, the insides are getting worn more quickly, but balance and response are good, and they'll be done about the same time as the rears, now that I've had the tires flipped on the rims.

I think the wear I've gotten out of these tires is typical for someone who asks all their tires can give. I had heard about the unusual temp/camber requirements and this was confirmed in on-track experiences by myself and Mike Schuster. They were used as they were designed to be.

frayed

Relax cthree, where'd all the attitude come from? Wouldn't expect that from a principal of this board. Now, rather than getting my panties in a bunch, arguing about the vagaries of who is gonna kick who's ass, and who's daddy is tougher, let me throw this out there:

On full blown ITS race cars, on both the E36 chassis as well the RX7's, RA1's shaved to 4/32's run about 1 second off the pace of Hoosiers at Road Atlanta. However, they are more consistent while Hoosiers have a small operating window, or sweet spot, in which to get some really fast laps in. This is why in enduro races you'll see racers go with Kumhos or Toyos, and Hoosiers for sprints.

For the above reason, and for many others, I still like Toyos or the Victos (not the Ecstas V700's though) over Hoosiers for hot lapping and DE's.

Now, if you want to take it one step further and brag about a hot lap that conquers all others, just go out and buy a used (barely) set of slicks for the Ferrari Challenge guys. I have a source for them; $75 each. However, you'll barely eke out a weekend of use, and you'll generate cornering forces typically beyond the design criteria of most street legal cars (leading to all sorts of problems), they suck in the rain, they suck when cold, they have a small sweet spot, give little warning when they go off, but you'll be in for a wild ride if you have the balls and skills to let it hang out.

Alternatively, if you have money to burn, buy a set of A3S03's. You'll go through a set in one session, maybe two, but you'll be blazingly fast. It's a 'trick' that some will use in qualifying sessions to turn one or two really good laps, then go back to R3S03's for a typical sprint race.

-------------

All that said, everyone has a different definition of 'Ultimate' track tire. For me, I'll gladly give up one second to save the considerable cost differential of Hoosiers, and get twice, if not three times, the longevity and more consistent lapping in with lowly Toyos or Kumhos.

And finally, 'test my theories?' I never stated that an under-rimmed Hoosier would not outrun a skinnier, properly rimmed Toyo. In fact, I stated the opposite.

j2k

First off.... you'd better check yourself on comments like these. Not only are you likely to find yourself eating a large portion of crow but its pretty bad form to start conscripting other people into your big dick contest... ahem.

Okay... that out of the way...

if Chico is looking for a dedicated set of tires for the track (as he has said that he has no intention of running them on the street) then it stands to reason that he's got or going to get a second set of rims. (Chico are you still here?) If this is indeed the case... then the point I was trying to make was that its a bad idea for myriad reasons to stick with the stock rims when you dont have to. The car is just plain better with wider wheels, even with the same size tires. I know this first hand. I've gone back to back with 225/245s Victoracers on the stock wheels and then on 7.5"/9.0" Volks. There's no question that the wider wheels felt better, were faster, and wore better.

I dont think anyone should waste your time with the stock wheels if you dont have to. If you can afford Hoosiers... you can afford some better wheels and a swaybar.

next...

Sphincter... I dont think we can look at NASCAR, F1, IRL, etc... for direction as to what makes for a faster wheel/tire combo without considering their rulesets. The thing to do would be to ask a race team from such a series "If you were allowed to run a wider wheel with the same tire, would you?"

frayed... have you driven on the NEW NEW kumho ECSTA V700? that is, those with a build date in the 02s? If not, I think you might give them a try again. They've changed the compound (again) and I think you might find them much MUCH improved. I used to tell people to flee from these tires like the plague and to stick with running Victoracers... but I have no problem recommending them now.


cheers,
jason keeney

frayed

Jason, I think we've exchanged posts in the past regarding PPW, and Jeff's skill's there (might be mistaken). Anyway, no, my experience with the Ecstas has been limited to the Victoracer compound. I understand from Rick at Kumho that they were intending to roll out the new compound on the exisisting (new) Ecsta V700 carcass by June 02. Mine were purchased in spring 02, and were verified to have the old Victoracer compound.

However, I remain leary, as I experienced the well known 'groove of doom' as was seen on the old BFG tires. It's pretty bad really. In addition, it seemed to take a lot of weight to get the tires balanced, and, after you overdrive the Ecstas, they take a looonnnnnggg time to come back.

But, at the prices of the Kumhos, I may give them a shot again. I look forward to hearing more about the new compounds on the Ecsta carcass. One thing for sure, is that Kumhos new construction is lighter than the old Victoracer.