[alanw]

Looking up hull speed on Google for a basic calculation - square root of the boats waterline times 1.34 equals hull speed. So, a 12' boat has a hull speed of 4.64 knots (5.34 mph), and a 16' boat has a hull speed of 5.36 knots (6.17 mph). That's less than 3/4 of a knot difference.

That makes sense since I remember expecting to haul ass in my 16' boat but really only gained about 1/2 mph in easy cruising speed over my 12' boat. Sure I could get the 16' going faster than the 12', but the amount of work required made it unsustainable for long distance for me anyway. I seem to cruise at around 3 mph no matter what boat I'm in.