Have a 2010 pontoon 20' with a 2010 90hp 4 stroke Mercury, prop is your basic 3 blade Alu 13 pitch Mercury prop. My numbers right now are, 2 people at WOT 5700 RPM's and 23mph. Thinking of going to a 15pitch and see what that does. I think RPM's will drop to 5300 but not sure. What do you guy's think?