Recommended RPM for Marine Power 350

" I have a 28' carver sant

" I have a 28' carver santa cruz that weighs alittle under 10,000 lbs with twin marine power 350 sport pac engines. I can't get it out of the water until I get to about 2600-2800 rpm. She runs 7-8 knots at 2200-2400 rpm and 10-12 knots at 2800 knots. I can do 15-16 knots at 3200 rpm. That's about half to 3/4 throttle. If I get to 3500 rpm. I can do about 17-19 knots. The engines seem to sound like they really shouldn't be going any faster. I opened it up twice and cranked out 22-24 knots at around 4000-4200 rpm. But can't hold it. The engines started showing signs of warming up. With these engines I feel I should be doing better than this. The hull is a Deep or Modified Vee. I don't understand!! What is the recommended rpm for these engines? Or is it just the boat?? "

3200 rpm is optimum cruise wh

3200 rpm is optimum cruise where torque and fuel are at best performance Wide open is 4200 rpm.
You never want to stay at wide open for more than a moment if even that. You might check your prop. The correct prop will incerease rpm.
clean bottom? Weight other than boat. How old are the engines? how many hoours?

" RX
CHECK YOUR TIMING
CHECK

" RX
CHECK YOUR TIMING
CHECK FOR EXHAUST RESTRICTION
DO YOU HAVE TRIM TABS? ARE YOU USING THEM?

I RUN MY 350 SBC ALL DAY AT 4200 WITH SHORT BLASTS TO 5500 (NOT RECOMMENDED). IF IT'S STARTING TO HEAT UP (HOW HOT) YOU MAY HAVE UNDERLYING PROBLEMS.

YOU ARE ALSO DEALING WITH INHERANT HULL SPEED. DEEP HULLS CREAT A LOT OF DRAG. THE MORE OF IT YOU CAN GET OUT OF THE WATER (TRIM TABS) THE FASTER IT WILL GO, WITH LESS STRESS ON THE MOTOR.

STEVE "