What can I expect with this motor?

[GMC406]

I was gonna biuld my own 400 in time when I ran accross a machine shop that was trying to get rid of this and needed a car trailer, I was trying to sell a car trailer and needed.....well didnt need but couldnt pass this up, 2000 dollar car trailer for 4500 dollar motor. Any way dude said aprx 425-450hp and 450 to 475 ftlb tourque, just want to know if anyone has anything similar, the 750 carb and aluminum radiator will get here this weekend so I can fire it up! Build sheet is as follows. Excluding little things(retainer wash jobs, gaskets, ect.)
406sbc Hot Street Manifold to Pan
511 GM 400 Block 2 bolt main .030 over
GM400 Crank
GM rods with ARP bolts
882GM Heads 2.02 Valves-Ported
Engne pro 2.02 SS Intake valve
Engine pro 1.5 chrome stem steel exhaut valves
Engine Pro Z28 springs
Sealed Power Flat Top Pistons
2m-30 Molly rings
Elgin Pro Stock cam kit 224* 234*@ .050 .488 .510 Lift114*LA
CH8 Durabond Cam Bearings
Engine pro Rod and Main bearings
Edelbrock performer RPM intake
Street Strip Bowl area
Sportsman porting bowls gasket match
flat mill to .010
competition 5 angle valve job


That is the just of it. What kind of power adders could I add in the future?