Tire changes again?

[kbrewmr2]

Looks like Spec Miata, 944-Spec and SpecE30 are changing - does this mean CMC and AI as well?

http://www.944spec.org/944SPEC/forum/general/13643-breaking-news-from-mid-ohio-new-spec-tire-for-13#13643

[GlennCMC70]

I knew this was coming, but was not able to say anything. I was told the same info first hand from one of the "testers". No date for CMC at this point, if there is one at all.

[ShadowBolt]

I knew this was coming, but was not able to say anything. I was told the same info first hand from one of the "testers". No date for CMC at this point, if there is one at all.

I would rather see CMC go the other way (I know no one gives a shit). A DOT tire that will last half a season or more. Who cares if it's a faster tire as long as we are all on the same tire and the tire does not fall off with a few heat cycles? Getting a faster tire will just give the fastest guys a larger gap between them and us mid-pack-slackers. Please can't we go back to 230/300, 16" tires, and lose the big brakes and the S197? What happened to CMC being Grassroots racing? I think we could double the size of our fields with these changes (plus going to a street tire that would last most if not all of a season). I love the time I get on track but I understand why so may stop racing after a season or two. The cost to race are double what I expected when I decided to run CMC. If we could get these cost down I'm betting we could bring in and keep more racers.

JJ

[AllZWay]

Why can't we get a tire that last longer and who cares about faster? We need a tire that is cheaper not more expensive.

[kbrewmr2]

fast, cheap, long lasting - pick two and even then there is still some trade-off.

Seems like they nailed long lasting with this one IF the data in the link is true, and it just costs a teeny little bit more than the RA1s do. Development of a new tire isn't free....

[ShadowBolt]

Why can't we get a tire that last longer and who cares about faster? We need a tire that is cheaper not more expensive.

Well said.


JJ

[Alien]

Seems like they nailed long lasting with this one IF the data in the link is true,

And that's the big IF. Would be nice to get it to last as long as the old RA1's, but I think at this point, that's wishful thinking.

IF it lasts the same as the (newer) RA1, and is priced ONLY a few bucks more than an RA1, THEN it won't be a bad deal. Price will be offset for not needing to have them shaved, and maybe make availability of places to buy them from a bit more open.

It doesn't sound like too a radical change of tire. They say it's still a DOT tire, so it's not a "true" slick. I'm all for letting SM and 944 be the guinea pig tho.

[rpoz27]

so they have tested it on 2000-2300lb cars with 150hp. Great. That info is worthless for 3000-3500lb cars with 260 to 360hp.... Just sayin'!

[David Love AI27]

No worries guys... "they" are going to do what "they" want... what we want doesn't ever matter...

[GlennCMC70]

I was never asked what CMC wanted. Some where in the loop and others were not. FYI, until someone announces that CMC is changing, don't assume we are. I have two new RA1's and am about to order two more.

[marshall_mosty]

I was never asked what CMC wanted. Some where in the loop and others were not. FYI, until someone announces that CMC is changing, don't assume we are. I have two new RA1's and am about to order two more.

I too was in the dark... and I have six new RA1's with two scrubs on the car...

[BryanL]

They are still allowing the RA1 in the other classes so I wouldn't worry unless you stash RA1's like some stash ammo.

[Alien]

Doesn't matter. I heard the new tire for AI/CMC will only be available in 18's.

*ducks*

[MHISSTC]

Doesn't matter. I heard the new tire for AI/CMC will only be available in 18's.

*ducks*

I hoped that was just a joke, but take a look at the sizes of Toyo RRs currently available:

205/50ZR15
225/50ZR15
P275/35ZR18

Maybe we could go back to the 4-lug 15" 10-hole Mustang wheels and 11" rotors with single piston calipers and drum brakes in the rear and call it CMC-Retro?

[Adam Ginsberg]

so they have tested it on 2000-2300lb cars with 150hp. Great. That info is worthless for 3000-3500lb cars with 260 to 360hp.... Just sayin'!

A ~3175lb, ~250rwhp CMC car on 2 different RR compounds was tested at BW in June of this year, in addition to a well prepared and setup AI car. An entire day of testing, in some warm temps (~92 degress, IIRC).

Toyo had 4 tire engineers onsite that day (and possibly the entire weekend), taking temps, pressures, notes, etc. IMO, they (NASA and Toyo) took this gig pretty seriously.

17's are supposed to be available as well. Not sure when, however.

I'm all in for the RR's.

[michaelmosty]

A ~3175lb, ~250rwhp CMC car on 2 different RR compounds was tested at BW in June of this year, in addition to a well prepared and setup AI car. An entire day of testing, in some warm temps (~92 degress, IIRC).

Toyo had 4 tire engineers onsite that day (and possibly the entire weekend), taking temps, pressures, notes, etc. IMO, they (NASA and Toyo) took this gig pretty seriously.

17's are supposed to be available as well. Not sure when, however.

I'm all in for the RR's.
What were the results? Who's car was it tested on?

[Adam Ginsberg]

What were the results? Who's car was it tested on?

Unfortunately, I don't have any copies of the test sheets, nor the results, as we weren't allowed to keep them. There were a total of 4 sets of Toyos bolted to my car - my original set (went out just to make sure everything was good on the car), a brand new set of freshly shaved RA1's, then two different compounds of RR's (also brand new).

S1 involved going out and running on my existing Toyos, making sure the car was ok. S2 was the fresh set of shaved RA1's to get a baseline. S3 was RR-A, S4 was RR-B. I was instructed to run the ENTIRE session (20+min), taking ~2-3 laps to get up to speed/temp, then run them as hard as possible for the rest of the session. Engineers were on hand to take tire temps/pressures, answer questions, and collect data sheets from the drivers after each session.

There were NO changes made to my car, at all, beyond bolting the rims and tires onto my hooptie. We used the same pressures I normally run.....AAMOF, that's exactly what the engineers wanted me to do.

The RR's were used in the 3 hour enduro that evening (not sure which compound, likely both but I'm not positive), but I don't know what the outcome was regarding longevity. Testing involved an SM, a 944, my car, and an AI car. It was a very interesting day, and I was quite tired (ha!) at the end.

For those "doubters" (DL and MFW) - I can tell you, honestly, from my discussions with the NASA and Toyo folks in the days leading up to testing, during the day of testing, and that weekend......they (particularly NASA) had no desire to repeat the previous R888 tire-change clusterfuck. It was very much at the forefront of their minds.

[ShadowBolt]

Adam,

Why is there a need to replace the RA1? Who is this change for.......NASA, Toyo, the racers? Ask the same questions we ask when talking about a rules change in CMC. I do like the fact thay we will not have to get them shaved. Opens up more places to purchase from.


JJ

[marshall_mosty]

Unfortunately, I don't have any copies of the test sheets, nor the results, as we weren't allowed to keep them. There were a total of 4 sets of Toyos bolted to my car - my original set (went out just to make sure everything was good on the car), a brand new set of freshly shaved RA1's, then two different compounds of RR's (also brand new).

S1 involved going out and running on my existing Toyos, making sure the car was ok. S2 was the fresh set of shaved RA1's to get a baseline. S3 was RR-A, S4 was RR-B. I was instructed to run the ENTIRE session (20+min), taking ~2-3 laps to get up to speed/temp, then run them as hard as possible for the rest of the session. Engineers were on hand to take tire temps/pressures, answer questions, and collect data sheets from the drivers after each session.

There were NO changes made to my car, at all, beyond bolting the rims and tires onto my hooptie. We used the same pressures I normally run.....AAMOF, that's exactly what the engineers wanted me to do.

The RR's were used in the 3 hour enduro that evening (not sure which compound, likely both but I'm not positive), but I don't know what the outcome was regarding longevity. Testing involved an SM, a 944, my car, and an AI car. It was a very interesting day, and I was quite tired (ha!) at the end.

For those "doubters" (DL and MFW) - I can tell you, honestly, from my discussions with the NASA and Toyo folks in the days leading up to testing, during the day of testing, and that weekend......they (particularly NASA) had no desire to repeat the previous R888 tire-change clusterfuck. It was very much at the forefront of their minds.

What were your thoughts? Or did you sign the NDA too?

[Rsmith350]

"Opens up more places to purchase from"

I think you might have nailed one reason for the change, no special equipment needed more tire places carry them= evil corporate profits

[Adam Ginsberg]

Why is there a need to replace the RA1? Who is this change for.......NASA, Toyo, the racers? Ask the same questions we ask when talking about a rules change in CMC. I do like the fact thay we will not have to get them shaved. Opens up more places to purchase from.

Unfortunately, I can't answer why there is a change being made, as I don't know the answer. I can only speculate that Toyo wants to move their product line "forward", if you will, and the RA1 might be considered "old" in terms of technology. Again, nothing more than speculation on my part.

NASA was adament the replacement tire had to cost close to the same as an RA1 (with shaving costs included), provide similar, if not better performance (longevity, grip, wear, etc), and require minimal setup changes. They (NASA) were also adament to include NASA racers in testing the new compound to get feedback from the very people they were selling their products to.

NASA, and Toyo, were aware folks were not always thrilled at having to shave tires to get better performance out of them. Not having to shave them will be very nice - nothing like spending ~$200 on a tire, then spending $20 to shave off ~$30 worth of rubber and throw it away.


What were your thoughts? Or did you sign the NDA too?

I totally dig the RR. Excellent corner exit grip, outstanding braking grip.....AAMOF, for the first time, EVER, I was able to really use my StopTechs. As in, they were hot and stinky coming into the pits, something I'm not able to do with the RA1. I really wanted to test brake lock-up with the RR, but had to be mindfull not to flat spot them as they had to be moved to another car after my session. Even so, I really hammered the shit out of both compounds, going wayyyyy deeper into some very high-entry speed braking zones, and never got them to lock up.

For example - T2 at BW, called the Buttonhook IIRC (Race #13, running CW (http://buttonwillowraceway.com/track-info/track-maps/)) is a sharp right that has camber on the far inside, is slightly uphill, but as you exit, it flattens out/is slightly off camber. Coming out of that turn, I've always had to feather the throttle, and provide some additional steering input because I can't put ALL the power down. Never could. Most CMC and AI cars can't. If you do, you'll spin the inside tire, and/or come out way too loose.

Ah.....yeah, forget that with the RR. Brake hard, turn in, get over the slight hump in the track, and go balls deep into the throttle, plenty of grip, upshift, WOT all the way to the braking zone of T3. Getting through the bus-stop, then the fast, high-speed right sweeper? Ooooo, yeah.

They came up to temp about the same time RA1's do (within ~2-3 laps), were very consistent throughout the session, and never felt like they dropped off. My fastest laps came at the end of each session, although it's entirely possible much of that had to do with the fact that I was able to "figure out" the tire, recognizing where it was working well, and able to take advantage of it. Usually, my car drops off in lap times the warmer ambient temperature gets. Not with the RR's.

I even told NASA, and the Toyo engineers, that I'd fun run CMC the entire rest of this season (we did the test in June) if I could get a set of the RR's and run them for the remainder of the year. Yeah, I liked 'em that much.

I'm going to hang out on a limb here.....my guess is we'll see a ~1-2 second per lap drop in times/track records, maybe more once people really learn the tire, and make changes. Only time will tell.....I'm may be completely wrong (wouldn't be the first time, and likely won't be the last).

[AllZWay]

I like the no shaving and glad to hear at least some testing has been done. I am leary of a faster tire equating to a longer lasting tire though.

[Wirtz]

Not sure I really feel like getting into this discussion but thinking a bit out loud;
More grip. Personally, not interested. I've run many series where the tires were more grippy than needed for the car / power level. It masks alot of driving issues and car setup differences. I'm not saying these tires will instamatic make every CMC car self driving. But I like having to work the brakes and steering to get a good lap. To me, lower grip and more forgiving can make for much more fun. But I guess I should shut up about it. I'm the one that always wished there was a good rally series in Texas...

You said you had to warm the tires for 2 or 3 laps. Were any tests done with our actual race routine? Stone cold tires, 1 outlap and then into race pace or even a standing start? How do the tires behave when they are shocked?

Good thing is as long as everyone is on the same tires, it is not as a big deal. No mater what tire it is, I still hope to be back out there playing again at some point.

Jeff

[michaelmosty]

More grip = more strain on the car = more wear + tear.

Why do we need more grip in a spec series?

Also, from what Adam said they help quite a bit under braking. With RA1's the 4-piston calipers don't give "that much" advantage b/c we are still at the limits of the tire. If we go to a better tire then that just makes the Big Brake Kits help even more and then drive the cost of the series up even more.

[ShadowBolt]

Not sure I really feel like getting into this discussion but thinking a bit out loud;
More grip. Personally, not interested. I've run many series where the tires were more grippy than needed for the car / power level. It masks alot of driving issues and car setup differences. I'm not saying these tires will instamatic make every CMC car self driving. But I like having to work the brakes and steering to get a good lap. To me, lower grip and more forgiving can make for much more fun. But I guess I should shut up about it. I'm the one that always wished there was a good rally series in Texas...

You said you had to warm the tires for 2 or 3 laps. Were any tests done with our actual race routine? Stone cold tires, 1 outlap and then into race pace or even a standing start? How do the tires behave when they are shocked?

Good thing is as long as everyone is on the same tires, it is not as a big deal. No mater what tire it is, I still hope to be back out there playing again at some point.

Jeff

Hi Jeff,

I think you and James have some good points. A tire that has more grip and last longer sounds like a car with more power being quicker and getting better mileage. Possible, but hard to pull off.

I agree with liking a harder tire that is a drivers tire. My favorite Nascar races are the ones where the tire falls off in just a few laps and you find out who can really drive. Like at the old Southern 500 races. I still like the idea of running a street tire that would last all season and would require driver skill (yes, even if that puts me further back in the pack). I guess with the money NASA gets from Toyo that is not going to happen. My tire ideas are all about getting more people into CMC. Cutting the tire bill is one way of doing it.


JJ

[ShadowBolt]

More grip = more strain on the car = more wear + tear.

Why do we need more grip in a spec series?

Also, from what Adam said they help quite a bit under braking. With RA1's the 4-piston calipers don't give "that much" advantage b/c we are still at the limits of the tire. If we go to a better tire then that just makes the Big Brake Kits help even more and then drive the cost of the series up even more.

So now we all need to spend $2500.00 just to keep the status quo?

JJ

[michaelmosty]

I just read the treadwear rating is a 40.
I'm no tire expert but if the RA1 has a rating of 100, how is a treadwear of 40 going to last equal to or longer?

[marshall_mosty]

I just read the treadwear rating is a 40.
I'm no tire expert but if the RA1 has a rating of 100, how is a treadwear of 40 going to last equal to or longer?

More rubber around the carcass that you don't shave away (9/32 tread depth to 5/32 that we normally have) = 55% of original depth. That is treadwear 100. If the RR's are molded to 9/32 carcass depth with a treadwear of 40, you will get approx 70% of the life of a full tread RR to a 5/32" RA1... However, I have no clue if the wear rate on the RA1 is linear when the tread blocks are above say 2-3/32"... That "might" even it out. Also, I guessed on the depth of 9/32"..


Just stupid numbers anyway... It's all moot until something in the rules changes... For AI, there has be ZERO chatter...

[michaelmosty]

I read on the AI boards that Toyo states depth to be 4/32".

[Wirtz]

Molded at 4/32 sounds good, like has been said, nice to not have to shave them. But I wonder what the plan is for rains then. Two radial tread bands and 4/32" means not so good in the rain. Saw someone mentioned the RA1 can still be used for a rain, but does that mean Toyo will continue to offer the RA1 long term as a rain tire? Not like we have been dealing with alot of rain lately...

[GlennCMC70]

More grip means what was said above - The need for big brakes is greater now. But if the tire chage was coming, we havethe brake upgrade behind us and not in front of us. This tire would have likely pushed us there anyways. More grip means more parts failures. More grip mean less skill needed to drive fast. Perhaps we should all go to a 235 and the S-197 can go to a 205 (ha, ha).

Treadwear is factored by how much thread is there to start w/. If a full tread is a 100, and a new slick is 40, sounds liek they accually havea similar wear rate (not wear rating).

Surely Toyo wants to make a tire folks want to run, even those folks who don't run a spec class. How many folks do you think run RA1's that don't have to? Not a way to sell tires - only to those who have to run them. I like the move. I don't like change just for change, but I do like this so far. No shaving is big. There will no longer be the "trick shave job" ala the "JB Special" at Vilven ( ;) ). I can now suport my local vendors even though they don't have a shaver. If it proves to last longer than the RA1, another plus.

Don't get me wrong, I'm not pulling a Todd Covini here and painting all this to look like a rainbow.... I do think we will all be happier once we change..... if we change. I talked w/ AL today and he said nothing about it. If I recall, CMC change about other classes changed. It could be coming, it could not be coming.

[AllZWay]

Not sure I really feel like getting into this discussion but thinking a bit out loud;
More grip. Personally, not interested. I've run many series where the tires were more grippy than needed for the car / power level. It masks alot of driving issues and car setup differences. I'm not saying these tires will instamatic make every CMC car self driving. But I like having to work the brakes and steering to get a good lap. To me, lower grip and more forgiving can make for much more fun. But I guess I should shut up about it. I'm the one that always wished there was a good rally series in Texas...

You said you had to warm the tires for 2 or 3 laps. Were any tests done with our actual race routine? Stone cold tires, 1 outlap and then into race pace or even a standing start? How do the tires behave when they are shocked?

Good thing is as long as everyone is on the same tires, it is not as a big deal. No mater what tire it is, I still hope to be back out there playing again at some point.

Jeff

Good Stuff Jeff.. I prefer to keep it driver series too...not big brakes and increased setup requirements.

[GlennCMC70]

Anyone like the BFG T/A street radial? Should be plenty slick!

[BlueFirePony]

If you all recall, when the 888 came out we were all told that World Challenge and entire other series were 100% behind that tire so we were all [insert derogatory reference] for questioning that despite our own hands-on. Same tune, different band...not sure I want to dance to this one either.

[kbrewmr2]

I just read the treadwear rating is a 40.
I'm no tire expert but if the RA1 has a rating of 100, how is a treadwear of 40 going to last equal to or longer?

treadwear ratings are more about marketing than actual grip levels - easy to skew up or down depending on who they want to sell to.

just ask any autocrosser on "140" treadwear tires....

[michaelmosty]

treadwear ratings are more about marketing than actual grip levels - easy to skew up or down depending on who they want to sell to.

just ask any autocrosser on "140" treadwear tires....
Isn't it called "teadwear"? Isn't that a measure of wear?
You could get 80,000 miles out of a set of 500 treadwear tires. Could you do that on RA1's or RR's?

[kbrewmr2]

there's a difference between "skew" and "just slap whatever the hell they want on the sidewall" - lulz

[BlueFirePony]

I just read the treadwear rating is a 40.
I'm no tire expert but if the RA1 has a rating of 100, how is a treadwear of 40 going to last equal to or longer?

treadwear ratings are more about marketing than actual grip levels - easy to skew up or down depending on who they want to sell to.

just ask any autocrosser on "140" treadwear tires....

Tread wear and traction ratings come out of independent tests - traction is a wet traction rating not dry or all-over grip.
To Ken's point though, manufacturers assign treadwear in a range based on the actual testing and their overall product line with contraints mandated by regulations (e.g. they cannot out right OVER rate their tires but they CAN under rate them). Also, the test for tread wear does not exactly map well to actual tread wear resulting in racing....the test is largely a convoy at relatively slow speeds that will not push most tires to their maximum operating range and will definately not see maximum "grip" level - and the testing is done by the manufacturer. 888 and RA1 have the same tread wear (100) and frankly that means nothing to me based on use on track.

[kbrewmr2]

looks like some early problems with the Toyo RR - something about having to be mounted a special way and even then tread delamination ala early Kumho V710s. Will post more when I see more than just random forum posts here & there. Seen enough stuff from 944-Spec users and people like Phil (of Phil's tire) to think it's an issue with the tire and not an issue with the early adopters though that's for sure.

[Crumpacker]

looks like some early problems with the Toyo RR - something about having to be mounted a special way and even then tread delamination ala early Kumho V710s. Will post more when I see more than just random forum posts here & there. Seen enough stuff from 944-Spec users and people like Phil (of Phil's tire) to think it's an issue with the tire and not an issue with the early adopters though that's for sure.


That brings up a good point. Are the inner and outer sidewalls the same? If they can't be flipped, that's a huge mark in the wrong column. It's easy to pull an extra 2-3 days out of a set of RA1s just by flipping them.