2002 Mercury 60/40 Jet problems

[STIKM]

Hi, I am new here and looking for some help
I have a 2002 mercury 60/40 jet serial #0T489730. I had water in the oil injection system and it took out the #2 cylinder so I replaced the power head, rebuilt the carbs and have the correct float setting of 9/16 inches (14.29mm), synced the carbs, rebuilt the fuel pump, checked to ensure the oil pump marks lines up and bled the lines, set the low timing (2 ATDC - 2BTDC) and max timing at cranking at 24BTDC. Have installed new plugs (BP8HN-10)and even tried a set of resistor plugs (BPZ8H-N-10). Ended up replacing the trigger and stator. I am tired of replacing parts that may be good. I have taken ohm readings on all three CDM and they are within specs. the problem I am having is the motor is hard to start and it only runs at 4900-5000 RPM's. Before the power head went bad the boat would run about 31 GPS speed up river. My friend has the same setup as I do and we use to run side by side. Now it only runs about 26 up river. Any idea what is wrong with this motor? Is there anything I have over looked?

[boats.net]

Was the powerhead purchased new, used or reman'd? What is the serial number from the new powerhead (is stamped on a freeze plug on the block)? Have you changed anything with the propeller? Does it seem to run fine or rough? Have you completed a compression test on the new motor? What did you previous motor run in RPM's?