Thanks for the link to the Penske manual - it'll take some digesting!
The KW Clubsport 514/800 spring rates translate to about 475/260 at the wheels. With that much forward bias and the narrower front tires (I was on factory 19" 245/265 PS2's instead of my r-comps) I expected a level of understeer that I simply didn't experience. What I experienced was that the front end was solid and planted and I could drive it anywhere I wanted without it even threatening to wash out.
What was really surprising was that the PS2's drove like r-comps with the suspension set up right. They didn't get even a little bit greasy and the grip was remarkable. They didn't build up as much heat as they usually do either.
I haven't looked at the tires since the track day to see how much wear they took, or whether it's even, but I'll report back later today or tomorrow.