cat 3208

I have a 1990 Searay Sundancer 420 with cat 375 hp 3208 engines.I have 22" by 26 pitch 3 blade props, Sea Ray says this is correct props for my boat when I gave them serial number. Boat is supposed to turn 2800 rpm at woot I am only turning 2500, had a cat mechanic check out engines and he said...