I've owned several smallblock chevy motors.
My LT1 idled at 17-20psi, 2K rpm was around 40psi, and WOT was 60ish+
My LS1 idled around 38psi, and WOT was 60+
My LS7 idled at around 20psi (just off idle, it would come up to 40-50), and WOT was 80+
Here is a live read-out from my LS7 for you:
http://www.youtube.com/watch?v=eYLRy7RT-QQ