Power from gt-40 heads and e303 cam on supercharged 5-0

How much power / tenths could i pick up from slapping a set of rebuilt stock gt-40 heads and a e303 cam on my stock 5.0l block, vortec supercharged with 8psi...73mm maf, 70mm tb, 30#ers, 255 lph pump, afpr, ported typhoon intake, x pipe-no cats, flowmasters, msd 6btm, 3.73's.......im thinkin about em if they are worth $400...for the heads....what do ya think??