I have a question for any tire experts here. I just finished a day at the Glen with only 4 track sessions. I have stock PS2's on my Cayman S. I started with 34psi all around and after the session the pressure had jumped to 44psi so I bled back to 38psi. After the next 2 sessions the pressure jumped to 41psi all around and each time I bled back to 38psi. I am passing on this info just to indicate that I was getting the tires hot, real hot in my opinion.

Anyway before I left home I checked tread depths on each tire and found 9/32" on the fronts outside and center and 8/32" on the inside. The rears were 8/32" outside and center and 7/32" on the inside edge.

After 700 miles traveling and the above mentioned track sessions, I check the tread depths again and found they were exactly the same, no wear. I would have thought there would be some measurable wear after the track sessions. Am I just not driving fast and hard enough on the track yet or are these tires just too good.

I can see some wear in the brake pads from this event.

I don't run my PS2's on the track any more but I'm told you want them between 38 - 41 hot. It doesn't surprise me at all that you didn't show any measurable wear on your tires. 4 sessions isn't that much mileage and that track isn't terribly abusive on tires.

Think about the great value your car is giving you at the track and start booking your track dates for next season!

It really depends on how hard you're pushing it. If you're driving hard enough to get a 4 wheel drift, or even just one end drifting (over/understeer) you will see significant wear with that limited track time, particularly on the outside shoulder of the tire.

Street tires last me about 3 days on the track. Track tires (R compounds) actually last me longer because they grip more/slide less, about 5-8 track days, depending on the track.

Greg

Stock camber in our cars puts the contact patch squarely on the road for street driving where you are not pulling high-G turns most of the time. So you will see your shoulders wear out on a track as you push the car harder and the forces generated roll the car onto the edges of the tires. As I have mentioned before, I like marking the shoulder and monitoring that roll to keep the contact patch from creeping too far over and cording my otherwise fine PS2s.

__________________

2007 Speed Yellow Cayman GT 2.7 (retired)
2008 Guards Red Cayman GT 3.4
"Carpe Cayman"

I agree with Greg. If you're not wearing the outside edges, especially in the front, it's because you're not pushing very hard. I corded my front PS2s in 5 track days and that's with swapping sides, proper pressure settings and driving at most, 90%. More aggressive camber settings would help, but PS2s just don't last long on the track.

__________________
Dan

Sounds like I'm no where close to the limit of what the Cayman can do yet.. I thought with all the heat I was generating into the tires I was giving them a pretty good work out. Joel said he was getting around 135mph at the bus stop and I was getting 130+. On the other hand I'm getting great millage out of my tires even with tracking several times a year.

If you're having fun, improving your skills, and nudging up against your comfort zone, you're pushing hard enough for a DE. Most here are "no where close to the limit of what the Cayman can do" and never will be.

__________________
Dan

I believe hard braking can heat up tires as much or more than agressive turning.

I am running 19" stock Conti's on the track on Carrera S rims on my CS. I've had 3 track days and I am showing significant wear on the outside shoulders of my front tires.

From what I've gathered in these forums, I will probably need some negative camber dialed in. Also, I expect that these Conti's might be good for a couple of more track days - might as well finish them off.

As far as replacing these with more track oriented 19" street legal tires (since I drive to DE's) - what would brand/type of tire would you all recommend that would fit on the factory rims?

Any suggestions and first hand experience with different tires would be welcomed.

I thought about buying a set of wheels and tires for just for the track, but right now I do not want to go with that expense - especially since my car, outside of track days, is mostly a weekend driver. Thanks!!

I just bought a set of slightly used PS2's offa Ebay for $400. Even if they only last an event or two its worth it to me as I end up chucking tires because the outside edges are worn down to the cords but the rest of the tire has plenty of depth left. For that price I'm not weeping when I have to replace them. Might get a cheap set o rims to throw them onto at some point.

G.

as track tires and tread wear, to this point, hasn't been an issue. The front outside edges are getting thin but no cords show yet after 10 track days.
What has changed is the ability of these tires to grip--on a dry track or wet track. their grip just seems greatly diminished probably from the extensive heat cycling.
Falken 615's are the next tire for me; the PS2 works well as a tire that can be driven to the track and driven on the track, but it seems a bit expensive for that role. I'll probably keep this set as a spare in case one of my street tires (PS2s) goes south.