Re: Minimum Planing Speed
Fr. Frank will probably chime in here with a technically correct answer, but I believe rake of the prop has a lot to do with it. Before I repowered, my Seafari would plane nicely at 12-13 mph with an ancient (but light!) 115 Evinrude running a 13 3/4 x 15 SST prop. Of course it's better balanced than a CC because helm is further foward and weight of the cuddy up front. When I repowered with a much heavier motor and a bracket w/30" offset, it would not plane below about 3500 rpm/25 mph with a 14.25x17 3B SS prop; a 14.5x19" 3B SS prop was a little better at ~2600/17 mph. This was a huge issue for me because I often like to be able to cruise at min planning speed offshore when the seas kick up.
Currently running 2 different Michigan 4B props, both of which plane easily @ 12-13 mph: 14x18 Vortex (Al) for heavy load planes at about 2700, and a 14.125 x 20 Apollo for light loads and a little better mpg, planes at about 2000. You have to be careful with the 4B props; some bass boat designs are BOW lifting! If description says designed for heavy offshore boats, it's probably STERN lifting.
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