I don't know why I didn't think of this forum earlier. Driving a Cayman I went to the Cayman Register first, but this is really a more general track issue and I've found members of this group to be very well informed.
I run PS4S on a Cayman and this year managed to cord the edges (after 13 track days) while I still had a lot of tread in the middle. Attached are photos of the left side pair and the right side pair. I try to run at about 35-37# hot which works well.
I'm not sure why. Pushing too hard is one possibility. Someone suggested I needed more sidewall stiffness but I always though the PS4S were fairly stiff; maybe I'm wrong. If so, I could use suggestions. A third possibility is this is just normal; tires and pads are consumables
. Anyhow, I am looking for comments, ideas, suggestions.