estimate hp

just got my 408w taken apart this winter and have decided to upgrade it, my old combo was sportsman block all machined, forged steel crank, eagle rods, probe pistons, 408 windsor, world sr heads, lightly ported, lunati hy roller with 218 228, 536 536, 112lsa, stealth manifold, 1.6 rollers, Bigs 750Hp DP, msd billet dist, 1\3\4 super comps, 7qt oil pan. new combo is same block only 5000 miles on new engine, roush 200 cast iron heads fully ported 0.500 on .in 245.5, .ex 179.2, 0.600.in 262.7,.ex185.4, 0.700.in266,.ex190. 65.7 chambers, 10.70 comp ratio, custom comp hy roller 236 242,555 576, 108lsa, vic jr manifold, same carb, headers etc!!, 69 mach1 c-4 full manual, wondering how much more power i'll have, old power was 400 flywheel and 380ft lbs@3100.:)

Wow, are they still making cast iron heads? I thought they leaked a little?