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Having a great time with my 2015 Cayman S, did a euro delivery, with some track fun!

I've got about 6k miles on my P Zeros with 4 laps at Nordschliefe (not pushed very hard), 4 20 minute sessions at Spa (2 dry, but don't think I pushed as hard as at MMSP Utah) and one 25 minute DE intro a couple weeks ago at MMSP West in Utah. That session I pushed very hard. I started each day at 30/31 psi. I thought that whenever I saw above 38 psi the tires seemed to feel a bit greasy. The DE guy in Utah (who is a 981 owner) thought that the 40 psi I saw at end laps wasn't too high. When I teched for the upcoming two day HPDE-1 course next weekend, my fronts are worn to 80/60 remaining (inside/outside) and 50/40 rear remaining. I've asked the local Utah Porsche service guy (who also does the track) about wear, he said increased wear on rears is normal for 987/981 type. (Incidentally, I've also used about 20% of the factory brake pads as well.)

I don't have time before next weekend to verify or change camber. I don't mind using up what's left of the rears but want to get the best wear out of the tires. I'm leaning toward starting each day at 29/30, and bleeding off as the tires heat up so that I hit a 37-38 psi on hot laps. Or, should I run a different pressure strategy to preserve the rears? While I've been told that I've got plenty of rubber left for the two days, I really don't want to be down to slicks on the rears in the middle of the second day.

Comments, please, as the HPDE is a non PCA event and I cannot assure I'll have anyone who speaks Porsche in my right seat.

Cheers!
 

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FIrst, I do not personally run Pirelli's. I use NItto's but the process is similar. I start with 28-30 psi cold tire pressures. As the tires heat up they will increase by 8 psi. I check my pressures after every session to keep hot pressures at 38 psi. At 40 psi, tire grip goes away.

My rears run hotter than my fronts by 2 psi usually. My rears wear out considerable faster than my fronts usually. I am not concerned with tread life since I run my track tires bald as long as no belts/core are showing. Normally, I scrap tires due to heat cycles and loss of grip before I wear all the rubber off.

Hope that helps.
 

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I use NItto's but the process is similar. I start with 28-30 psi cold tire pressures. As the tires heat up they will increase by 8 psi. I check my pressures after every session to keep hot pressures at 38 psi. At 40 psi, tire grip goes away.

My rears run hotter than my fronts by 2 psi usually.
Nittos here as well. I start at 29F and 30R. They seem best at around 37F and 37.5R.

Question for you Iceman: This is my first set of NT01s and I have only 2 track days on them so far. I've read Nitto's are good to the cord and don't heat cycle out. Sounds like your experience with them is different?
 

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I had heard the same thing that many people never considered them heat cycled out. My experience appeared to be otherwise.
I ran 8 track days putting 40 heat cycles on them over the course of 1 year. My tread was gone but I still had rubber on them. I started fighting for grip down .2 G's which was unusual. I purchased a new set and bingo with new tires I was up 3 seconds per lap over 1.7 mile course which is substantial. So, now I buy a new set every year despite the way they look.
 
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