I had an 88 offshore with a 88 225 Evinrude hung on th transom. This outboard had a 15x17" aluminum prop and would easily spin to 6000 rpm and top out at around 43 mph. This boat had no hardtop, single tank, no curtains, etc (not real heavy and not too much wind resistance)
I also had an 92 explorer with a 2000 250 Yamaha EFI. 15x17" ss Yamaha saltwater series prop would spin to 5700 at 42mph. I also tried a Michigan 143/4"? x 19" prop that was fine except for when the boat was heavily loaded. With a full load the boat took a long time to get on plane. With this prop I it would top out around 5500 an top speed was 4300. This boat had hardtop, bracket, full canvas, dual fuel tanks, etc.
Hope this helps