Attn: Hoosier R6/A6 users

[997S22]

Thanks for the explanation.  I note and share your caution about advising others to use certain pressures, especially newer drivers.  My goal was simply to share some information that was shared with me that I found helpful and thought may benefit other RTR members - I think that is one of the best reasons for these forums.  Other RTR members should start with Hoosier's recommendations, but if they decide to cautiously experiment with other psi's they may find lower pressures deliver more grip, but our set ups are all different...

The recommendations were shared with me last year by an individual involved in preparing cars for Grand-AM, IMSA,Porsche Club Racing and DE .  Their on-track testing of the optimal set up for Hoosier R6's was done with pro drivers running several laps at each of various pressures and found the best lap times came with lower pressures.  The best lap time results were not consistent with the psi's that gave the best tire wear or most even tire temps.  My friend said to me, "do you want even tire temps or the best lap time?" These findings were used by winning cars in last year's club racing.  Like your situation, was it the car, the driver, the tire pressures? Likely the combination of everything coming together.

I had been told by many experienced drivers that Hoosiers had to be kept between 38 & 40 psi hot, so I was skeptical of this new recommendation.   I asked around and it seemed most hadn't tried lower pressures and were so concerned and cautious that I was hesitant to even test dropping my pressures 5-7 psi as the friend had recommended. Then as I indicated earlier, I decided to test into it cautiously, dropping just 1 psi at a time, testing 2-3 pressures per session over a number of track sessions doing several laps at each pressure. I was sharing the car with my son that day and we both had 5 sessions so we had plenty of opportunity to test each pressure.  After we got down to the recommended pressures, we were both certain the car had much more grip with lower pressures, but to be sure it wasn't because the track was warming up or some other variable we then started testing increasing the pressures again.  With just 2-3 psi added back in we both noticed the grip deteriorate, so ever since we keep them lower.  In our experience , for our car 38 psi seems to be the "break point" - at 38 psi or higher the tires slide much more than below that.


I had this same discussion 2 weeks ago with a fellow I was parked next to in the Lime Rock paddock.  He tried lowering the hot pressures for the Hoosiers on his track prepped Evo from 38 to 35 and told me his data aquisition system showed his lap times in the next session improved by 2 seconds.

Again, if you or others don't want to try psi's outside the standard 38-40 psi recommendation that's fine, just sharing some information and experience that I thought might be helpful to other RTR members who are interested.