I am looking for any ways to bump up the power in my 509. It is a merlin II with merlin heads (iron 320cc). It has a 5140 kellogg crank and 200cc tall dome srp pistons. I have a victor jr 454-r intake and a pos 850 marine carb. I know that if I bump up to a diff carb and get rid of the water in the headers I can pick up some. I am turning my alum b/c impeller to 5600 rpms and I want to turn it to 6300-6500. Short of swapping pistons and heads what can be done to reach that goal?? Any help would be appreciated.