What should I expect from 450hp?

Here's one.......is your clutch slipping ?? I am of the opinion that you should be desintegrating your tires when you mat the gas, 3.23's are not too tall for that to happen.

Decades ago I did a Pontiac 455 in a 77 Trans -Am, rear gears were 3.08, maybe 2.90 something, also a 4 spd car. At idle in first, mat the gas and tires went up in smoke instantly, or if from idle, you layed into the gas slowly to the floor, at about 1500 rpm the the tires would brake loose and up in smoke. I always ran out road before the tires would stop spinning, just before the 3-4 shift.