Need help please,no power 5.0L mercruiser v8

Idle fine but it will takeoff only at full throttle and wont takeoff if we are 4 on the boat.Will rev at 3600rpm max @ full throttle on water

The boat has a 5.0L engine,Propeller is 16pitch and 4 blade.Boat is 20feets long.

Hull clean?
Not carrying water in foam under the floor?
is ignition fully advanced? Say 26 degrees advance by 3500 rpm?
igntion components in good shape? Cap rotor wires and plugs?
fuel supply to carb -tank pickup, anti siphon valve fuel filter clean?
carb condtion clean and working? Does it idle ok ?

below us a general list


http://forums.iboats.com/forum/engi...6-list-of-possible-causes-of-low-wot?t=295070

The foam is dry.
Engine will idle 1000rpm and sometime 600rpm.
It has brand new fuel 87octane
Propeller is brand new with 16pitch fours blade.
The hull and outdrive is super clean,alway been out of water after the drive and flushed.
The outdrive ratio is 1.50.They use 1.50 for 5L and 5,7L engine
boat is not overloaded since factory seat is for 9 people and we are 3-4 on board
Engine is not overheating.

I will look at the website you sent to me and look every of them.

has no power between 2400rpm-3200rpm and max wot is 3800rpm-4000rpm sometime,take aprox 30sec to reach 2400rpm to 3200rpm even 45ec

I just found out my gas hose was kinked,could it be this?

BINGO fuel starvation, test ride time

No change.Still no power

Change the Dist cap and rotor if they are older along with the dist pick up. What is the serial number?