prop size.

[kh0432]

I have 70hp on a 16" Cobia Sea Scout center console. It has a 13 1/4 X 17 prop and will only turn 3200 rpm at wot. Owners manual says wot should be 4500 -5500 rpm. Any suggestions on proper prop size? Thanks, Keith

[normman]

I would think a 15 would be a good start instead of the 17.