1972 Demon 340 engine mods

I was thinking to advance it because my Duster is all in at 2200 but its 470 big block with over 11:1 compression...

This car now behaves as if it had two natures, its SLOW and gutless under 3000 rpm and wakes up over 3000. Really likes to rev high, it pulls to as much as you make it turn, I tried 7000 rpm gear shift and it felt great. I just dont know how far it can be pushed with those cast pistons, not too far I suppose.