I am up to 100 runs on my first set of 25B's. They still have tread material and are still sticky. I think the people who said 75 runs max were believing the road racer stories. I did reverse the fronts. Any other explanations?
Mark
I am up to 100 runs on my first set of 25B's. They still have tread material and are still sticky. I think the people who said 75 runs max were believing the road racer stories. I did reverse the fronts. Any other explanations?
Mark
1990 Van Diemen, the Racing Machine, CM AutoX, 2016 Frontier
You can try to make a street car into an autocrosser or you can do a lot less work and make a race car into a great autocrosser
I haven't tracked number of runs, but we're on our first set Hoosiers and I'm very happy with wear so far as compared to my S2000 where it was 60 runs max.
You would be surprised at what putting on a new set does for your times. The year that I went for the solo national championship I couldn't seem to get the car to turn the way I wanted. Tested and tested. Had about fifty runs on them. Put a new set on for the championship and the car was transformed.
They may be quick, they may be sticky, they may have tread, but they are not as fast as new. One or two weekends will make them slower. In a race of thousandths, that counts if you want to win.
I have no idea how many runs a 25B is really good for with max grip. My problem the last 10 years has been "calendar" time required to even get to 50 runs. My newest set is 2 years old and probably has less than 50 runs. However, now that I'll be active again the first event will be on new tires and the guess is a new set mid season and another for Nationals.
Dick
CM 85
My experience with R25 tires 16 years ago was quite different. I must be really hard on tires, or maybe it was the Texas heat.
I found that the grip when they were hot stayed nearly the same, but as they got older, they had to get warmer before the grip came in. During my last autox with them, the grip didn't come in until halfway through my last run. That was the 12th run on that set, with about 8 months from first to last run.
If I recall, I ran 11.5 psi front and 13.5 rear, and I bled them down between runs to keep the start pressures constant.
New tires are awesome, but they are only awesome once, and they get harder just sitting there in the garage.
We consistently get to about 120 runs before cords.
When the question is asked, "how many runs you can get out of a set?"
Well, if the guy(s) beating you is on new(er) tires. Then you need new tires.
Nick M.
Driving - your car if you'll let me.
Always NEW tires for Solo Nationals then move them down to run National Tours/divisionals the next year, then as they wear down/slow down, the next year they are used for local events to keep the seat time up. This requires extra sets of wheels and tire softeners like Formula V Traction Treatment and now Goat P from Thor Industries for even better stickiness. And keeping all the mounted tires in a heated space (away from sunlight) like my basement garage. They are thrown away when there is not enough rubber to soften anymore.
Jim
My experience is very different from many of you. I'm with Neil on this, for the most part.
The R25B stays grippy longer than the old R25A. But after 3 events, you should feel a dimunition of grip.
I found that the # of runs was generally not an important stat (although I did keep records). Much more important was number of days (unless there were hours between runs). So heat cycles is more what you are looking for.
By 5 to 7 events, my co-driver and I could feel a very significant loss of grip, but still very useable for local events. By 10 to 12 events, the tires are not particularly useful.
Another issue is that with a correctly set up autocross FF, the rear tires go off faster than the fronts. Thus constant twiddling with ARBs and tire pressure was necessary. After 10 events, I often could not twiddle enough to get the signicant oversteer out of the car.
And then when I got new tires, I had to go back to my "good tire baseline".
BTW, this is why the PAX doesn't work well with race tired cars except at events where everyone (all classes) runs new tires.. The street tired cars have a big advantage at local events where everyone runs older tires. Older street tires are much better than older race tires. Yet the stock and ST guys would strut around trash talking mod guys.
EDIT: The exception to the importance of runs vs events (heat cycles) are Test and Tune events where you can put 100 runs on a set of tires. In that case, the tires are trash right away or after another event or two.
Last edited by Jim Garry; 03.05.12 at 12:39 PM. Reason: add info
Jim
I wish I understood everything I know.
I am probably just becoming a better driver w/ practice, but I was very pleased w/ some of the grip and turning ability of the tires w/ close to 100 runs. It was shirt sleeve weather so tires held heat sitting in the sun between runs.
I know I will need new ones soon. Is there anyone who discounts the Hoosiers?
Mark
1990 Van Diemen, the Racing Machine, CM AutoX, 2016 Frontier
You can try to make a street car into an autocrosser or you can do a lot less work and make a race car into a great autocrosser
No.
Jim
I wish I understood everything I know.
Jim, you have been at the flat top of the learning curve for a long time. Remember Mark is still on the steep part of the learning curve. Wait until he bolts a new set of tires on the car. Wheee!
Dick
CM 85
Fell off the flat part of the learning curve due to inactivity and hoping to climb up again.
Jim Garry:
"The street tired cars have a big advantage at local events where everyone runs older tires. Older street tires are much better than older race tires. Yet the stock and ST guys would strut around trash talking mod guys."
You can catch the stock/ST guys at your local events with the newer softener - Goat P from Thor Industries. Jeff Colegrove (FM National Champion) loves this softener. It has a really bad odor so apply it outside - one coat and wrap for 24 hours is all that is needed for up to 12 runs in one day.
Jim
Note to self, things I learned about my new CM car today.
- Tires last three times longer than FS Mustang tires.
- Tire pressures are 1/4 FS Mustang pressures.
- Goat P is good for your old tires.
I think I am going to like CM
Dick:
"Does Goat P result in more grip than brand new tires?"
Obviously not because there is not as much rubber on an
old tire, BUT it will give you more grip than a NON-TREATED
old tire. This is a savings as you can postpone buying new tires
but you just have to invest in more wheels. Always use NEW tires for
Lincoln Nationals (solo heaven) and then treat them for all other events.
Back to treating my E Mod Jeep tires (Formula Atlantic) for the Dixie NT this weekend.
Jim
Member, F600 Committee
Doug, you were only getting 30-35 runs out of the 295 A6's on the Mustang???
With careful rotation and flipping them on the rims at 35-40 and 60-65 runs, I was able to get right at 90 runs out of mine...but, the sequence was 0-20 runs = awesome, 20-40 = less awesome, 40-60 = acceptable, 60-80 = sketchy, 80+ = why am I doing this, again?
I've used stuff like Formula V (Goat P like stuff) on DOT R's with mixed results, it is interesting that it evidently works better on slicks.
Anyhow, yeah, you're going to like CM. I have a grand total of 12 runs in my car (before the slave cylinder took a dump) and have no regrets.
I did exaggerate, but only slightly. We get 40-50 on summertime concrete and up to 90 on asphalt (with flipping). The big issue down here is extreme heat and abrasive concrete. Just when I started running the Mustang we went from mostly asphalt sites to 90 % WW II concrete. I do love the grip on concrete, but it can be a tire eater.
One our sites is so abrasive that at a divisional last summer, 110 degree heat + 90 second courses plus two drivers had some folks going to cord on fairly fresh A6's (total runs in the 25-30 range).
I will have to get some Goat P. It will occupy a place of prominence in my garage.
The only way to get discount hoosiers is to drive faster than everyone around you. Unfortunately, your competitors often have the same plan!
Regionally, we used 1.5 sets this year. I replaced the rears partway through the season because they had gone off. The replacement rears were takeoffs from a road racer. They had 4 marks on the sidewall, so I'm assuming they had 4 events or 4 heat cycles. It worked well enough for 1-2 pax finishes the entire year. We probably treated the tires every other event. 1 coat the day before with plastic wrap over the tires to force the Goat P into the rubber will do the trick.
I ordered Goat P. HDM Co had it for $17, but they charge $16 to ship.
Mark
1990 Van Diemen, the Racing Machine, CM AutoX, 2016 Frontier
You can try to make a street car into an autocrosser or you can do a lot less work and make a race car into a great autocrosser
I think I can get goat pee free. I've got a friend with a goat, just got to figure a way to catch the pee. Might be worth the $33 not to have to chase the goat.
Heck, George, I'd pay the $33 just to watch you chase the goat...
Hey, if I could get enough people to cough up $33, I'd fill a can for me and give the extra away. We could all have free goat pee only it would cost you $33.
Hate to stop the goat pee thread but I have a question for Jim Murphy about GoatP tire conditioner:
Jim, how many FF size tires will one can of GoatP treat? Also, how many typical runs and/or weeks between treatment?
Thanks,
Dick
One coat on the tire the day before the event is fine. I find it lasting our normal 6 runs per driver on a 2 driver car for a regional event. After you paint on the Goat P wrap the tire in plastic wrap and it will force the chemicals to soak into the tread rather than evaporate.
The 1 quart can should last you most of a season.
Yes, Dick, I am in the steep part of the curve, committed to being a winner I love finding new things a FF can do that would have totally upset my STX car. I was drifting to the outside after a 90 deg turn, like I had taken it too fast, but I was able to turn in a bit more and the car went where I pointed it. I probably wasn't going fast enough Lots of seat time between now and Nationals.
Mark
1990 Van Diemen, the Racing Machine, CM AutoX, 2016 Frontier
You can try to make a street car into an autocrosser or you can do a lot less work and make a race car into a great autocrosser
Still running on my first set of Hoosiers, over 130 runs. Havn't tried the Goat P yet; it has been raining out here. Things were a bit tail happy today so I softened the rear bar a bit more. I thought I finally beat the hot Subie, but when I reviewed the on car video, I found that I DNF'ed the Slalom. Darn
http://www.youtube.com/watch?v=v_S8MecabWA
Mark
1990 Van Diemen, the Racing Machine, CM AutoX, 2016 Frontier
You can try to make a street car into an autocrosser or you can do a lot less work and make a race car into a great autocrosser
If you mean the chalk on the course side of the cones that is the SF area tradition. In the old Northern California Sports Car Council (NCSCC) rules the lines define the course. The cones help you find the lines. In the "real old days" slaloms had to be done as fingers in order to have a line rather than just cones.
I got my autocrossing start in NCSCC around 1975. SCCA autocrossing became popular is SF shortly thereafter.
By the way, SF and other California autocrossers had a large impact on the course design rules now in the SCCA rules. The term used at the time was "miniature road race". Due to the very "large" number of Corvette clubs in NCSCC and the small primary site (Alameda County Fairgrounds in Pleasanton) multi-lap open courses were the norm. In my Stock Datsun 260Z speeds typically stayed comfortably in second gear with no lugging and no redline. Lots of fun since you got to do every corner two or three times on each run. Great for learning the car. California drivers won a LOT of SCCA Solo championships in those days.
Dick
CM 85
Last edited by Dick R.; 03.26.12 at 1:32 PM.
If you're going to use Goat-P or FV Compound, or similar, it may be wise to get ahold of the MSDS. Naphthalene is either the prime or only ingredient. Bad stuff.
If you use it, please wear thick rubber gloves and only do it outside. Stay upwind. Don't get sloppy applying to the stuff to your tires ... i.e., don't get it on you.
Jim
P.S. General info on MSDS: http://en.wikipedia.org/wiki/Material_safety_data_sheet
Jim
I wish I understood everything I know.
mark, note to self: Lower visor BEFORE you start the run
dave
I noticed a rather LARGE pit in my closed face helmet visor one day. The next event I realized why. The RWD car launching in front of me spun the tires a lot, pelting me with gravel and grit. Thankfully my visor was down otherwise the rock would have been in my eye. I now ignore the grid workers trying to get me to be on the bumper of the car in front of me, and I drop the visor before I leave my grid spot if I'm in an open top car.
On the "how long are R25's sticky?" Both myself and a local ex DP driver think you have 2 months from the time the mold release is broken. For autocross is seems to be a time thing more than a run thing. As they age, they turn into R35, R45 and eventually R60 equivalent compound. You can get a lot of runs out of an R60
From my track side service days: a customer had been running the same set of Yokohama 008's for 4 years and they still had tread left. He purchased a new set of Hoosiers and picked up at least 4 to 5 seconds a lap at Summit Point. He was grinning from ear to ear about the grip and sensation. not so happy they didn't last like the Yokohama 008's
[QUOTE=TedV;339125]I noticed a rather LARGE pit in my closed face helmet visor one day. The next event I realized why. The RWD car launching in front of me spun the tires a lot, pelting me with gravel and grit. Thankfully my visor was down otherwise the rock would have been in my eye. I now ignore the grid workers trying to get me to be on the bumper of the car in front of me, and I drop the visor before I leave my grid spot if I'm in an open top car.
I am with you on that one.
On the "how long are R25's sticky?" Both myself and a local ex DP driver think you have 2 months from the time the mold release is broken. For autocross is seems to be a time thing more than a run thing. As they age, they turn into R35, R45 and eventually R60 equivalent compound. You can get a lot of runs out of an R60
I hear you here, too. I am close to ordering another set of tires. I will try the goat P at least once.
Mark
1990 Van Diemen, the Racing Machine, CM AutoX, 2016 Frontier
You can try to make a street car into an autocrosser or you can do a lot less work and make a race car into a great autocrosser
138 runs on my first Hoosiers and I have now ordered a new set.
Mark
1990 Van Diemen, the Racing Machine, CM AutoX, 2016 Frontier
You can try to make a street car into an autocrosser or you can do a lot less work and make a race car into a great autocrosser
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