Guys, I wanted to mention to the challenge drivers about the new Hoosier R100 Slicks. We had three tire blow outs last week at the Hutchinson Island on Hoosiers(a 355,a 430, and a 360). It has been discovered the Hoosier slicks are beading on the inside of the tire and creating a tire failure. I talked to Hoosier about it. They say the problem is low tire pressure and/or wrong camber angle. They recommend a cold 23 psi and hot 31-32 psi. I think the camber angle they recommend was 2 degrees. You can call them for the exact camber angle. But, I say defective tires. I think they have some issues with The new R100 tire or they made a bad patch of tires. If you are running Hoosiers on a Challenge car keep a close eye out for a seam to develop on the inside of the tire between the wheel and the edge. If you start to see it, then a bubble will start to appear. If you see the seam, I would not run the tire. It's on the inside of the wheel, so it is hard to see it. It's real a shame because these R100's are really good tires. I thought I would bring it everyone's attention.
Between Pirelli and Hossier... With the same pilot, the same 430 Challenge and the same track what is the difference of Lap Time with these two tires??? Thank you
The FCRA has completed extensive testing of all 355, 360 and 430 tires and found no issues when run properly. Everyone was running them at temps and camber of pirellis and they are different. On the 430 the differences between the pirrelli and Hoosier are minor. The Pirellis on stickers are about .5 seconds or so faster for the first 3-4 laps, they level out for a while and then sharply fall off. The Hoosiers also are fast new for 4-5 laps and then settle in and stay a bit more consistent than the Pirelli. The Hoosiers do wear faster if you don't watch temps and camber. The good thing about Hoosier is they are super responsive to the FCRA and have a factory rep at each race taking data. They are getting feedback from every FCRA race and have told us they are willing to design a tire specifically for the FCRA objectives. I personally really like this. The FCRA has begun discussions with Hoosier about designing tires for the FCRA that will balance speed with longevity. The FCRA and Hoosier may design a tire that sacrifices a little some speed for more longevity to reduce costs for the FCRA 2012 season. If the FCRA stays as a spec tire series next year the competition will be equalized.
I think hoo hoo hate us. We do everything wrong and have been repeatedly lectured to by hoo hoo. We use pyrometers to set tire pressures and test test test. Hoo hoo says we use the wrong pressures and the wrong tires but are setting lap records and winning racers are the ones who do it the wrongest. What do we know? We are just a just a bunch of SCCA slugheads. So what blew rear tires? Over the years I have had many defective hoo hoos. Most have been in the bead. And I have seen that bubble before. I have seen it as the radial belts blowing up causing the bubble and failure.
This is caused by low tire pressure. Excessive camber will aggrevate it. The damage usually occurs in the first 1-2 laps as at low pressure the wheel will pinch the sidewall and cause a cut on the interior of the tire. It may take 8-10 laps for the damage and failure to become apparent. If you are starting bellow 22 psi you are taking a huge risk regardless of Hoosier or Perelli tires. Drivers must be extremely carefull on their out laps to avoid excessive load on the tires, avoid any curbing and keep speeds down on high bank corners. this is a know issue with any of the low profile slick tires started at low pressure and high camber angles.
the Hoosiers are dimensionally different then that of the spec Pirelli. The tire diameters are different - meaning less than the Pirelli. Does this play into tire failure? I don't think so, but going from a Pirelli to a Hoosier and not changing your set up might.
I don't know of anyone running 22 psi cold. Most drivers are running Nitrogen without air and setting pressures at 31 sometimes 28 cold. The hoo hoo's (I like that FBB) are great tires. Just be on the lookout for the seam. Blowouts are occurring on the rear tires.
I recall the spec Challenge pressures for the Pirellis were 25F and 23R - are you saying that Hoosiers need higher pressures? I run my R100s at the same pressures as the Pirellis so cannot believe that a 1 lb lower rear at 22 psi is the cause of these problems?
I just got the newest generation of Hoosier slicks for the 355. I have say they are fabulous. They are consistent, Great grip, Wonderful feel and No issues. I have to say they have out done themselves. Go Hoosier Tires!!!
