Tire Question

[erlrich]

Hey gang -

I just was wondering, are there any potentially serious problems with using different types of tires at each end of the car? I realize there may be issues related to differing levels of grip, but then the whole point of this exercise is that I was trying to think of some quick and easy ways to get a little extra grip in the rear, and it also just so happens I have a pair of old Hoosiers sitting around taking up space.

Thanks.

[timelapseracing]

Earl,

At MARRS 1, I did that and the car was almost undriveable. It would go to instant oversteer due to the different levels of grip. I have been since told that if you have mismatched tires, to make them different side to side, not front to back. I didn't try it, just bought new tires, but it seems to make sense.

Jason.

[erlrich]

Earl,

At MARRS 1, I did that and the car was almost undriveable. It would go to instant oversteer due to the different levels of grip. I have been since told that if you have mismatched tires, to make them different side to side, not front to back. I didn't try it, just bought new tires, but it seems to make sense.

Jason.
[/b] Jason - this was with the better tires on the rear? If that's so, it would be exactly opposite of what I was thinking (and probably therefore 100% logical); I would have expected to pick up a bad understeer in that situation. Hmmm....guess that's not something I want to try for the Sat qualifying session, huh?

Thanks.

[JamesB]

I would pick up two hoosiers and run all 4.

[spnkzss]

When I used to run 225/45s on the front I would run 185s out back to help the car rotate. That was more because my car didn't rotate well.

[erlrich]

I would pick up two hoosiers and run all 4. [/b] I had actually thought about that James, but the pair I have are actually 1 1/2 year-old S04s, so running those with a new pair of S06s probably wouldn't be much different than running those old Hoosiers with my Toyos. And, when I do go for better tires I'll probably go with Kumhos or Hankooks - I really like the fact that they both support regional racers with contingency money.

The real problem is, the tightwad in me doesn't want to toss 6 perfectly good (relatively speaking) Toyos in order to gain a second or more - I still haven't quite gotten past the idea that I CAN race within a budget :rolleyes: .

[JamesB]

Troll around for some takeoffs then. you might find something.

[JohnRW]

We've run entire 12 hour enduros with different tires on the front and back...and bagged class wins doing it. Kumhos front, BFG's back. BFG's front, Bridgestone's back (that should date it, huh ?). Etc. etc. etc. Pitted with some ITB guys at at the first Summit Point 12 Hour who had, for qualifying and a big part of the race, three different brands of tires on the car at the same time.

They're just tires, fer chrissakes. Experiment. You'll probably find a blend that you'll like.

[Joe Craven]

I've mixed and matched tires, especially in long enduros when maximum grip and performance wasn't the key factor to win a long race.

I also did it at the last minute before a ITB sprint race where I had made a lot of suspension modifications including stiffer shocks, sway bars and springs. Car was understeering really bad which I couldn't fix before the race. I stuck Goodyear GSCS (Hoosier grip) on the fronts and Toyo RA1s in the rear so I never did get a chance to test. I expected the Goodyears to grip much better than the Toyos but what I didn't consider was the time differential it takes the 2 tires to warm up and get to maximum grip. In turn 3, which is an off camber corner of the race when we were just getting up to speed at Thunderhill raceway , the rear end came around and I nearly spun out. I kept my foot in it and just barely managed to keep the car on the track and not lose any positions. Car got really wide in the corner and I think nobody wanted to pass a car on the verge of spinning!

By the end of the 1st lap, Toyos came up to temp and the car handled beautifully. I worked my way to 4th position and my lap times were within .1/sec/lap of the best laps of the top 3 finishers.

So yes, it can be done but be careful.

[RSTPerformance]

We run different sized and "aged" (S04/S06/whatever) tires front to rear without any issues.

We run 225's in the front and whatever 205 we can scrounge up for the rear. Sometimes we have used the old style tires in the rear and we have not ever had any issues.

In the rain or "intermediate" conditions we run very different :wacko: setups. One race we even ran slicks on the front and Dirt Stockers on the rear. It WAS the hot setup for that race. We are always thinking about running Autocross tires on the rear as they don't come up to temp nearly as much as the front.

Raymond "We will try anything or use anything if need be ;) " Blethen

PS: As for tire brand check with the Hoosier rep out in your area... we have exxcellent support on the east coast at every track we have run at nationaly and regionaly. We also have had excellent contingency awards from Hoosier.

[erlrich]

Hmm, sounds like even if it is possible to make work, it's probably something best left for a practice day.

So, now I have a new set of V710s on the way...if I were still married my wife would probably divorce me. See what you guys have done :(

Raymond - I was under the impression Hoosier only offered contingency awards to national level classes. Was I wrong?

[RSTPerformance]

Raymond - I was under the impression Hoosier only offered contingency awards to national level classes. Was I wrong?
[/b]


In the Northeast they also offer it to NARRC ONLY races. We have lots of other regional races not counted towards NARRC points thus they do not get contingency. The NARRC series though is the biggest though so I am sure thats why those are the only ones that count toward contingency. You might not have anything now in your region/location but maybe you can change that!!! Hoosier IMO is a great company willing to support its racers. :035:

Raymond