Fishy 68,
My buddy has the same car as me and built the same engine as yours based on a 340 block with no stroke, same cam intake and heads worked just about the same as yours.
His Dyno'd at 460 hp at 6200 and 450 ft of torque before 5000 rpm.
Yours should be over 500hp and a torque monster before 5000 for sure!!!!!
I almost went with the Iron Ram Heads, they are a super great choice and have tons of power potential for sure!!!!!!!!!!!!!