What would be the typical speed of a heavily loaded 18' square stern Grumman on deep, flat water (no current) with the following two-stroke outboards: 6 hp, 9.9 hp and 15 hp? Thanks.
My 18' Scott freighter heavily loaded has topped 18MPH, but not happily. It's most content at 14 or 15 MPH, which is found at about 1/3 throttle instead of floored.
I strongly suspect I need more bite on my prop, since my 15 HP Tohatsu is pushing the least amount of boat drag it might have been designed for, I figure.