I have also have a similar post on the "Setup" board, but I thought I would put it here as well since it is a prop question at this point. Boat info is below, and I have two questions. I have started over from 3.5" PTP a couple of times and when I get to a certain point, I lose RPM, speed, and a little water pressure (low 20's psi). Last weekend I raised it 1/16" at a time and the results are below. Could I be losing lift at this point causing more boat to be in the water?


2000 Bumble Bee 180 ProVee (18', 1050 dry hull weight)
2019 Mercury 175hp ProXS 4s; 23p Fury Prop; 10.5 Hours on engine
PTP RPM Speed
3.5 5740 66.3
3 7/16 5750 66
3 3/8 5760 66.3
3 5/16 5740 66.1


Also, I have been playing with numbers on the prop slip calculator at go-fast.com. At 3 3/8" PTP I have 3% slip and 5760RPM which is in the correct operating range for this engine. Even if I got 5950 rpm with no more slip I would gain less than 2MPH. If I went down to a 22 pitch prop, and got 5950 RPM with 3% slip, I would lose speed and only have 65MPH. Am I not better off staying at a 23p prop with more MPH and less RPM, but still in the safe operating range at WOT? Am I missing something or should I put it at 3 3/8" PTP and go fishing?