Next step for more HP (383BB)

Hydraulic roller cam, at 230 ish duration, should be over .550 lift. Lift pretty much=flow and flow=power. If you want to stay with flat tappet, the Comp XE/HL hydraulics or the Hughes cams should have you at .525 or so at 230'ish durations. Try the XE275HL. Similar to what you have WRT duration, only more lift from more aggressive profiles. I wouldn't go more than that on duration, unless you go to 4.10 gears.

Have the heads flowed and make a decision on porting based on those numbers. Did Todd at moparts give you any info when you purchased the heads? Without objective data, you're just firing blindly. If you're near Gurnee IL, or willing to take a trip, I can flow your heads, and make recommendations accordingly from there. S/F.....Ken M