Just wanted to see what your guys' input is on this....When i flatfoot the boat i am only at about 42-4300 rpms.  Its a 21ft with a 460, msd ignition/dizzy, a berk 12jc a pump.  I hear most people running closer to 5k rpm's.  Is there something that needs adjusting to get more out of it?  or is that normal?

x2 with GT, you may be getting close to floating valves much over 4,500 w/ stock valve train components.

p-jet

It has some mild work done to it.  It has roller rockers, a mild cam, its bored .030 over with upgraded pistons and rings, full msd ignition & dizzy, harman marine tt headers, edelbrock performer intake w/ a holley 800 carb.  There is usually at least a 30pk or two in the boat. I have checked the timing with a light and everything seems accurate.  When i hose run it in the yard when you rev it the rpms runs all the way up to 5800-6000.  Obviously being in the water will put a different type of strain on the motor so i dunno.  I was just checking.  It seems like there is more in her and I didnt know if maybe there was something i was missing

FWIW here is a little more rookie .02 from me. My new motor will pull an ab to 5400(so far, low 70's.) that's about 500 on the ricter scale. At first I felt a little . Then I started thinking I'd have to make about 600 hp at sea level, to end up with 500 herel. Imo you need a gps # to go with the r's(especially if you don't know the imp. cut) Also if you have re-cammed and you are running a aa that might be part of the problem. You may benefit from an A cut'ish.

I was told it was an A impeller.  12jc-A pump.  now i have no idea if somewhere along the road that has been changed or not but that what i was told was in it.  I am running low-mid 60's on gps.  Im thinking maybe the rpm gauge is set to 6cyl.  I will  have to check that when i get it back

If the tach was set for a 6, the tach would have read like 5500 RPM if it were really running 4200...Just so you know 

GT

I was told it was an A impeller.  12jc-A pump.  now i have no idea if somewhere along the road that has been changed or not but that what i was told was in it.  I am running low-mid 60's on gps.  Im thinking maybe the rpm gauge is set to 6cyl.  I will  have to check that when i get it back

It sounds like you may have an AA, if there are no problems with the engine.

Is what possible?  A  aa cut will provide the most mph per rpm. 60+ out of a 21' boat at 4200 doesn't sound quite right to me but wtf do I know.

im turning 4,300 rpms no gps number yet though....bbf but i just moved the gas pedal more closer so i can get the secondaries to open...i was messing with it today and realized just that...where my pedal was set at i couldnt push the pedal down far enough...but i guess to answer your question my bbf is turning around the same rpms...on a stock single point ignition no gps numbers....18ft boat

the engine is off a fresh rebuild and has been thoroughly gone through.  I may have an aa impeller however how would i be able to run low-mid 60's with a aa impeller?  Is that possible?

I have a Kona, 18 ft, Berk 12JC, with an AA. Olds 455, 4800 rpm, 65 mph. 
(however, this will probably change as I just had the boys at JBP bless the pump)

if you have a A or AA could be about right depending on how strong it is.  Check for the secondaries opening.   Mine do so ~4200.