SG_M3

agreed, but have you ever run 48 psi in a hooiser?

Larry Herman

On my 2700 lb RSA I could tell by the feel (and the times) when the pressures were at 38 (good stick but a little soft), 40 (fastest but ready to go off) and 42 (hard and greasy).

It is possible that such a heavy car might be able to benefit from the OP's higher pressures. That and a gauge that reads a few lbs high could explain everything.

One other question is where the OP is running time-wise as compared to others. That could explain things too.

Brian S

Good valid points, unfortunately the gauge is right compared to 3 others (give or take 1-2)

pyro is in the 220 area for the rears, 190 for the fronts (obviously left/right bias depending on the direction I am driving)

I teach at this track and have the DOT tire record of any car around this track with this setup and it is stable for 60 minutes of driving so they do not overheat or ever become greasy although they do take 6-7 laps to get into where I can really drive the car properly but as also stated, my car is slightly loose braking and isn't ideal in faster/longer high grip corners although that is mostly feel. the segment times are still good.

Another GT3 owner was using R6's with 32/36, ran my setup and went faster as well.

Perhaps I am compensating with high pressure to achieve a looser setup that should be done in alignment? I run 8.08in of rear toe, 0.02 front toe-out, 2.8 front camber, 2.7 rear camber. both stock bars set to hard (most inside hole)

Sadly I don't have access to an air source so I can' to go up once I get to the track, but I will try my setup today and then try the 38ish area. I have always liked a few pound bias toward the rear though so maybe 35/38 or something similar.

On a side note, I keep the R6's on my car (daily driven maybe once a week or so) so they see rain and cold temps every once in a while. I imagine most of you remove the tires but have you seen any problems with keeping a set on for a couple of months with enough track days to cycle them out?

va122

Don't do it. They are not designed for the street and are thin for lower rolling resistance and they easily can be damaged by road debris and fail.

Larry Herman

It sounds like you are certainly driving it hard enough then. One thing that I find strange is that it takes 6-7 laps for the tires to come up. I found that my Hoosiers would be up in 1/2 a lap, and I frequently set my fastest qualifier on my 2nd or 3rd flying lap. If it were me, I'd try 37/39 and set my front bar a notch or 2 looser. They only way to learn is to try things. I certainly would be interested in knowing how it worked out, from both a time & a feel standpoint.

SG_M3

Agreed, 4 corners an hoosier is up to grip. In my experience, Hoosiers peak in lap two, lap 3 is nearly as fast, then its downhill from there.

Brian S, How many heat cycles do you get of R6's?

mark kibort

I have been running the R6's for years and have found peak lap times with hot temps 44f and 48r on a 997 GT3.

that would be about 115F if it was "C". It was a joke Dave, relax!
I think we all know it was pressures he was talking about . knuckelhead!

onefastviking

No way !
But I have seen other peoples gauges 10 psi off before, and since we sit here on the computer asking 'what temps do you run" without asking if you use a gauge from WalMart or one from XYZ Racers Suppy I find it interesting.

Brian S

I ran 44/48 and was about half a second off my usual time, the tires may be too old and the track may have been slow but it was a good baseline.

i tried 35/38, it was decent but did not throttle steer like i am used to and I didn't read the comment about the sway bar before going out today and that would have given me more steering so that could have helped. overall 35/38 was about 0.7s slower than 44/48 (run about 15 minutes apart to let the tires cool down)

I tried 35/35, the rear of the car was just too planted and then seemed to change over the run. i didn't even time this one.

I usually drive for 30-60 minutes per cycle because the R6's seem to cycle out before the tread is gone so my # may not be accurate for DE guys that run 4 20 minute runs per day but I usually get 10-12 and then they get really loose and it seems like you can see a discoloration on the sidewall from heat around this time.

I normally use an autozone special gauge, cheapest thing possible since it seeems to be accurate compared to others (even a snapon dial) although it is about 4 higher than my porsche dial gauge. The key is that it is always this one gauge.

analogmike

I hate when that happens.