I hear 27 psi cold works great.

What have you found?


KT

Are these the road race or autox tires from Hoosier?

Yes, DOT-R Hoosiers road race tires, not the ax ones.

I heard 27psi from a 911 racer out at Sears last night that was running in a 3 hour enduro.


KT

Only problem with that Trekkor, is the 911 guy is going to get more heat in his tires with the handliing of a 911 vs your 914. Also more time to heat the tires in a 3 hour enduro than in your 20-30 min practice session.
Is there any info on the Hoosier website or tire rack?

Also Greg Welch has been running Hoosiers on his 914-6, he might be able to give you some input if he is lurking.

See my answer on Pelican, you cross-poster you.

Well here it is, so you don't wear out your mouse:

31# cold (ambiant temp) has worked good for me. I got that from Hoosier info brochure that Tire Rack sends and also from a Hoosier rep at the track. I've run as high as 34# cold and had good results. When I tried going lower 26#, 27# they felt like they were moving around under the car. All this info is for a 914-6 whick I know is what you drive. 911's are heavier and can run less pressure.

I ran my Hoosier track tires at 30psi at Thunderhill. They were at 135-6 degrees by the time the session ended.

It was a mild day.

Grant's suggestion on the autox tires was good.

Ran 225/45-15 Hoosier R3S04 on 8" rims 1900 lb car. 40 PSI hot
temps on tires were 140 across the face -2 degrees camber.
60 hot laps total for the day. Very nice feed back and tons of grip. I was lapping ths same times as a new EVO on Yoko RA-1's He is regarded as damn fast.
Ambient temps for the day high 80's surface temp was warm not hot.

Which year Hoosier are you asking about? I'm still running 05's I bought on close out. I havn't tried the 06's yet and I understand they are a different belt which would change the pressure requirements.

R-5's

Here's a mock-up with the new wheels!

Click to view attachment

Click to view attachment

Can you tell I'm excited?


KT

lmao, trek....

Grant, I believe you are right,,,,they do look vaguely familiar, don't they

don't know what you guys are talkin' bout.

The 40 psi hot was not as good as the 710's.

I will try 30-35 psi hot next month and report.


KT

I have a hard time believing that Trekkor, that's a perfect range for the Hoosiers, 39 - 40 hot. I've never heard of anyone saying the 710's were faster than Hoosiers. You should have been a couple seconds faster on the Hoosiers. You're going to be rolling around on the Hoosiers at 35# hot. Anyway, I know you're just experimenting so have at it.

Drew, do you have to run the Hoosier's in your race class?

I may try and run at the "Porsches at the Point" event at the end of Oct.

If we are there together I would appreciate if you rode along with me and gave me some feedback.

I wish I ran video on my final session at Laguna.
The track was pretty clear as there were maybe 8 cars running.

I was very calm and *everything* was working with the 710's.

For example: turns 5, corkscrew and 10 had tire squeal and a little push with the Hoosiers. Not with the 710's.

The Hoosier's are 1/2" wider on 6.5" rims compared to the 710's on 7" rims. I really think I had the pressures ALL wrong for my car and my driving style.


KT

I don't have to run Hoosiers, they are talking about making our class a spec tire next year and using the Kumhos. They will be running Kumhos next weekend at Buttonwillow so I should hear how much faster or slower they are then. I still have two sets of Hoosiers to burn through so I don't have Kumhos to experiment with. I hope to see you at Infinion. I've been having so many small problems with my car lately that I'm not real confident of making any event for sure. I keep thinking, next year.

710's or Victoracers?


KT

I was given a used set of Toyo's today that still show the wear bars, so I'll test them , too. Yarrrr...


KT

710's. The whole point is to save money but it looks like the 710's will only save me about $120 a set which is nice but not major savings. I wish they had gone with the Toyo's, if we're all on the same tires it doesn't matter how much slower they are.

How many track days do you get out of your Hoosier's?

I have 4 on my 710's ( 21 sessions ) and they still are very new looking and the grip is better than my new Hoosiers.

I'm trying to get 8-10 days out of them.
Got 8 out of the last set plus several a/x's. Maybe 40 sessions plus 20-30 a/x runs.
I still have two of them that I run as fronts. So add another 12 a/x runs...

KT

I keep track of my Hoosiers by heat cycles. Everytime I go out and bring them up to temp is a cycle. I usually get 14 good cycles before they start falling off. I usually run them up to 18 to 20 cycles which is 4 to 5 track days give or take. The most I've gotten out of a set was 25 heat cycles. My Hoosiers rarely look used up when I get rid of them except for heat discoloration, they just don't stick anymore.
If I was just doing DE and didn't mind my times falling off I could get several more days out of a set, but when you're fighting for position in a race, old tires don't cut it.

Hmmm...I've got 10 sessions on my Hoosier's now ( 10 cycles ).
After one more track day they are going to start falling off?

By how much? 1-2 secs per lap or worse?

Is this typical of race tires in general?
I hear Toyo's get better and better until the cords show


KT

After you pass 15 heat cycles they will slowly start feeling a little looser in certain corners. It'll continue till you're 2 seconds off your normal pace and there's no denying the tires are just not gripping anymore. The 944 guys use Toyo's as their spec tire and they say the same thing, they get faster as they get old. The Hoosiers aren't that way.

What are your lap times at Sears and Laguna...TH if you ran there?


KT

T-Hill 2:12.1
Infinion 1:55.2
Laguna 1:48.2

Laguna time is lifting in T5 for the sound meter.
T-Hill and Infinion I've only been to once so far.

Those times are great!


Much faster than me...


KT

Trek,

I ran the 2006 Hoosiers with my son at the last 2 PCA weekends at thill plus a Santa Rosa Autox. As of now I have ~ 24 heat cycles (2 weekends with 2 drivers at thill) plus 6 autox runs at your home course. The tires did not go away at all - my last run Sun am was 2:10.87 and the car stuck. Key I have found is to keep the rear below 41 psi, above 40 the rears get slippery. I start out cold @~33 front and 35 rear. As the day progresses and heat builds up I go out ~34 rear and return ~40lbs.
Hope this helps.
Greg Welch

Nice to see you posting again, Greg.

Do you have any track days planned for the end of the year?


KT

Trek,

Yeah, I just got too busy...anyway I am contemplating the hpde event at Infineon late Oct. Planning on your autox in SR on 10-14 also. Love that course.
Sounds like you've gotten lots of track time...nice rims too !!
Greg

Andy or anyone....

Do yo think using tire warmers such as the Chicken Hawks would help tire longevity? By that I mean when you come in and pit, could you put on tire warmers and keep the tires warm, thus putting off the cool down of the tires and also the heat cycle?

It probably isn't a one to one correlation, but since my wife and I run the car, we are like Greg where we have double the pleasure, but also double the heat cycles. It seems like the tire warmers would pay for themselves in one year IF they actually helped to keep the HC's from occuring.

Or would keeping the tires warm all day cook them?

Bill P.

NO.

Chill them quickly with towels kept in a cooler full of ICE/WATER. The tires release "chemicals" when hot. This makes the tire harden. If you shock them cold.. you will get more heat cycles out of them. Several "veteran" racers do this down here with POC. They 4-5 more heat cycles out of their slicks this way. You also see SCCA AutoX people "wetting" the tires for this same reason in lanes.

Greg,

Your numbers are DEAD ON for what I have found for 914's running on Hoosiers at NorCal tracks. By your lap times it appears you are not a "back marker" and trying to learn your "tires"



B

It's all black magic to me. Cooling the tires to stop the chemical release makes sense. Don't know about the shock treatment angle. I do know that if it were shown to work there would be deep freezers in the transporters at the POC events Worrying about tires is not something I'll need to do for a while. When I do get my car back on the road I may give the Kumhos a try just for the heck of it. It appears that the spec tire proposal for my class has fallen apart because the top dogs couldn't get the right size to fit their humungous rims. Poor bastards.

OK I finally figured it out Trekkor. Your being paid to sell 710's on the side. How do the rest of us get in on that action?

(WOT) BTW good news out the city. Your excellant work is now known by the best real estate agent in the city. You've got business - I'll give you the connection.

Thanks Randal.

Are you coming out to Sears on Friday?


KT

Just got back from Sears.

I ran a 2:00 today.

How'd I do it, you ask, as that is a full 6 seconds better than last time and the track was cold all day?

I ran the Hoosiers at 35 psi hot. Stuck like crazy. Very predictable.
Textbook rollover on the shoulder.

They felt squirmy on the first lap or two of the morning before they came on.


KT

What did you start at cold Trekkor?

28.

Hey Trekkor, want to get rid of those Hoosiers now?

NO CHANCE!!

What I would like to do is have a fresh set of each, R-6 and 710's that are heat cycled and test them both all day in perfect track conditions.

Who wouldn't?


KT

OK- fast foward to Sears this past weekend.

The same tires have another full track day on them bring the total number of cycles up to 20-

The track surface was colder i believe.
But as Andy said, they were 2 seconds slower. I was running a 2:02 at my best.

The track temps made certain turns feel uncomfortable.
1-2, exit of 6 and 10.

i will keep tseting.


KT