Well I got it to pull to 4350, made a few minor changes and here are the numbers.
520 hp and 633.4 ftlbs. at 22.44 lbs of boost. I put the air turbine on it and it was pulling 1024 cfm through a 600 Edelbrock. I wonder how it would respond to a 750?
That's about as hard as I dare lean on 100,000 mile cast pistons. Engine is still intact.