Looks like the 60fts liked the lower tire pressure.
I was just thinking... and I think there's a chance the car might want to be shifted sooner. Try shifting the thing at 6000 rpm and see what it does. I'm thinking that big torque happy engine will torque its way right through the rpm range, and may even run quicker. (just a thought)
Knowing who spec'd you cam, I'd say it has a fairly high lift and a relatively short duration, and might respond very well to the lower shift point. It might also help explain why your car torques its way through the 2nd half of the track so well.
Good Luck!
