Gooyear and Hoosier Race Slick Heat Cycle data, For anyone interested in compounds Options

[nine14cats]

I thought I would post what I'm seeing for Heat Cycle (HC) and tire longevity out of the different compounds and brands I have been trying out on California tracks. So far this year I have tried:

Goodyear bias ply slicks in R600 compound

Hoosier bias ply slicks in R45A compound

I'm running pretty big sizes on a 2400lbs car with 23.5x11.5x16 fronts and 25x13x16 rears, but the compounds are supposedly the same for the different tire sizes on the product lines. Tracks driven this year have been Thunderhill, Infineon, Buttonwillow and Laguna Seca.

I started on the Goodyear's with the R600 compound. This a harder compound than I have run in the past but is part of a mandated spec series I plan on running later this year or next year. Cold characteristics are that they need 2 full laps to heat up. What I found is that once heated they feel very similar to the R430 Goodyear compound. The R600's felt great through 16 HC's but what was even more impressive was that I was able to get 27 heat cycles out of them before they had a severe degradation in lap times (2.5 seconds at Thunderhill on a 3 mile config). I ran the tires another 10 heat cycles before they developed a dime sized cord patch on the right front. All told that is 37 HC's before cording and 27 HC's before significant lap time degradation.

I am currently testing the Hoosier R45A compound on my car now. In back to back tests lap times confirmed that my car is 2 seconds quicker per lap with this softer compound compared to the Goodyear R600's. This is not surprising in that the R600's are a much harder compound than the Hoosier R45A. However, Hoosier does not make my tire sizes in the R55 compound. I will be tracking the HC and handling of these tires and will update the Paddock when I have more data. I will then switch to the more traditional Goodyear R430 compound that is used most often. This should give us a little data on how the HC and tire wear characteristics compare with the different companies and compounds.

Bill P.

[Joe Ricard]

Bill That is absolutley what I was talking about.
So comparing these tires to A3S05 Hoosiers. where do the two compare.
or is there just no comparision.

[J P Stein]

Bill That is absolutley what I was talking about.
So comparing these tires to A3S05 Hoosiers. where do the two compare.
or is there just no comparision.

Jose:

I'm not Bill....thank God (IMG:style_emoticons/default/biggrin.gif) , but I have some info.

I talked to Hoosier about the capabilities of A3SO5 VS the R35 compound slicks....asking which had more grip & which heated up more quickly.
The short answers to both were the R35 slick.

[nine14cats]

Hey Guys,

I seem to recall a few people posting that they would get 12 - 16 heat cycles on a set of Hoosier Dot-R's before the performance fell off on the track. I have never run them so I don't know what the butt dyno says or when they cord.

I do know that the Victoracers Doris and I ran at the beginning of our racing "adventure" would last about 4 time trials of a dual driver car, but they got pretty greasy when running too close together (i.e. back to back sessions).

Hopefully one of the Dot-R crowd will be able to give us some insight.

I wish I could try the R35's, but since we've gotten a little faster and we're pushing the car harder, we would burn up a set way too quickly for the expense.

Bill P.

[drew365]

Thanks for the info Bill. Please keep posting as you get more data. I may get bumped up a class soon and if I do I'll have to go to slicks to be competitive. As for the Hoosiers. On the R3S04's I get about 12 to 14 heat cycles before I start to feel them go away. I usually run them to 20 heat cycles but my last set I ran to 27 HC before they corded. My car has been down so much the last year that I just bought my first set of R3S05's on close out so I have no data on them yet nor on the S06's which just came out. One of the POC hot shoes is complaining that his S06's felt great the first day and went away big time during the second days race.

[9146R]

Bill - I have run nothing but Hoosiers. Even at 20-24th heat cycle mine were plenty sticky as long as the pressure (in rear) did not go over 40 (hot). Like Drew - corded mine after 27 cycles. Ran several PCA events with my son (back to back) I did NOT find them to go away....key in that situation was to bleed some air out when hot ~ 2 lbs down to 38 prior to going out for 2nd driver. I am debating going with either R305S, Avon Tech RA or slicks. I wonder if my car at 2100 lbs can get the G600 temps up enough to really stick. The softer compound would be better but tire life is limiting factor for my budget. Question for the forum - does the G600 tire stick and corner better than the Hoosiers ? Thanks Bill for jump starting this topic.
gw

[nine14cats]

Hi Andy,

Why is your sanctioning body thinking of re-classing your car? Spanking too many butts? (IMG:style_emoticons/default/laugh.gif)

Greg,

The R600's may be too hard of a compound to heat up quickly. For our 2 driver 914-6, we ran the canti's from Goodyear in the R430 compound or the Hoosier cant's in the R60 compound. The R60 compound has been superceded now by the R55 compound. The R45 compound seems to work with 2 drivers at BW but at THill we would overheat the tires in back to back sessions. The R60's (R55's now) and the GY R430's worked the best for us as a tire choice on the teener.

Bill P.

[9146R]

Bill,

Thanks for the feedback ! I will have to make a decision prior to Thill in late July. Also, great post on the mental aspects of racing. Agree 100% about the challenge in staying focused lap after lap no matter the conditions, traffic, distractions.
gw

[nine14cats]

Hi Greg,

Here are some links to the canti tires and the negative camber selections some of us have used. If you switch to slicks, you more than likely will need to take some of the neg camber out of your setup. It appears that on the canti's at least, the GY's like almost no camber while the Hoosier canti's take some.

Race Tire Dynamics

Info on Slicks

Goodyear Vs Hoosier Slicks

Also you can search under "John Rogers" and "Racer Chris" (Chris Foley) who have a ton of experience on canti's.

Bill P.

[nine14cats]

More tire test data....this time for the Hoosier R45A compound. 23.5x11.5x16 fronts and 25x13x16 rears...

The R45A's game me 19 heat cycles (HC) before going off big time. These tires were used during extremely hot track days, 90+ degrees at Thunderhill and 104 to 106 degrees on a 3 day weekend at Buttonwillow. Maybe someone can chime in with experience as to extreme track conditions significantly degrading the HC lifetime of these tires. As previously posted, I got 27 HC's out of the harder compound R600 Goodyear's before they fell off significantly in performance and 37 HC's before they corded.

Tire wear on the Hoosier R45A's is excellent and uniform across the tires, so it looks my last camber adjustment did the trick. At the next track day I plan on running the two compounds back to back in run sessions to see how far the Hoosiers have fallen off in lap times. There is still plenty of rubber on them.

Bill P.

[grantsfo]

Isnt heat cycling competely dependent on conditions? I could AX my Victoracers all day and never get a true heat cycle from them. Conversely when I had long sessions at Infineon in 100 degree weather the tires finally started hooking up after a few laps. I'm thinking the big tires may be working against me on my car in shorter events. They are perfect for longer track sessions

[nine14cats]

Isnt heat cycling competely dependent on conditions? I could AX my Victoracers all day and never get a true heat cycle from them. Conversely when I had long sessions at Infineon in 100 degree weather the tires finally started hooking up after a few laps. I'm thinking the big tires may be working against me on my car in shorter events. They are perfect for longer track sessions

Hi Grant,

I am in total agreement with you about HC's being dependant upon conditions. I would have to say that I'm probably looking at feedback from the track contingent versus the AX contingent. A 25 minute session on a 3 mile track in 65 degree weather will still HC a tire versus a 40 second run at Marina Airport. My R250 Goodyears for AX (the softest compound GY makes) were stone cold after each run at Marina when I went to an AX earlier this year at that venue.

I was curious to see if anyone had heard or had first hand experience of what the track surface temps did to the HC life as the temps went up. In other words, can you get 27 HC's out of a set of tires when the track temp is 85 degrees versus 19 HC's when track temps get 110 degrees plus. I'm not sure anyone has logged data, but someone might have.

For AX's I haven't heat cycled out my tires....i've always worn them out. For the track the opposite has been true, I alway HC them out before they wear out.

Thanks,

Bill P.

[Brett W]

Why aren't you running a R430 from Goodyear? The 600s are too hard for most short sprint races. How long are your races?

Take a look at the Avon Tires. I beleive they have a compund in between the R430 and the R55. My driver seems to think they feel better and last longer than either tire, plus the Avon seems to have more grip towards the end of its life.

[nine14cats]

Why aren't you running a R430 from Goodyear? The 600s are too hard for most short sprint races. How long are your races?

Take a look at the Avon Tires. I beleive they have a compund in between the R430 and the R55. My driver seems to think they feel better and last longer than either tire, plus the Avon seems to have more grip towards the end of its life.

Hi Brett,

I'm running the Goodyear R600 tires due to the fact that this tread compound and manufacturer is the spec tire for the race series my car has been built to. In Northern California there are a few spec series that are gaining momentum. The thought of the spec series is to keep the costs down (yeah...right)...but in my case, locally there are several GT level cars. Instead of running THE stickiest tire or THE hottest engine combo, the group is trying to organize spec level drivetrains and consumables.

My class, GT-L is a class where you can run a GT level prepared car but you have to run:

1. Motor that has stock internals and induction.

2. Headers are spec at 1 5/8 inch I.D.

3. Weight with driver at race end has to be 2300lbs.

4. The spec tires are Goodyear 23.5x10.5x16 fronts and 25.0x13x16 backs in R600 compound.

I also run other series where there isn't a spec tire, so I had a few sets of Hoosiers left over from last year that I've been playing with.

The main idea is to keep the motor rebuilds and tire wear to a minimum. And with the stock induction and the header size requirement, HP is basically limited to ~300HP in a 2300lbs car. Still fun and trying to keep the costs reasonable...

The class is growing as there are ~6 cars built for the series and another 3 I know of being built for next year. The Porsche Racing Club runs inside of NASA under it's own run group. The 911 Toyo Cup series cars have really taken off and are a few years ahead of the GT-L series in participant growth. But there are several folks in GT2 and GT3 looking at moving to this series when their current motors need renewal.

It's alot of fun getting the car ready. And I'm a "show me the data" kind of guy, so I'm always writing down what I experience and observe to share with everyone.

Thanks,

Bill P.