my 20hp rude moves my 16' skiff just fine, no need for experimentation
my dad did tell me a story however about him and his brother butting a 75hp on a johnboat in the del bay, both of them getting flipped overboard , and the boat running around the bay until it ran out of gas.
I had a Merc Mark 25 on an alumium boat rated for 7.5 hp.It was a little hairy with just me [I probably only weighed 170# back then] but it was fun.The boat broke apart in the bow after a couple of years and I got a Duranautic that was rated for 20hp. That old Mers Hurricane was fast.I had 6 or 7 props for it two and three blades from its hydroplane days.With the right prop that little boat used to blow right past my friend 13 Whaler with a 33 hp rude.Seemed like the boat was doing 35MPH+?
took a buddys boston whaler about 16' with a 90 honda to pecker heads (island beach st park) one day to surf. pulled in behind the park trimmed the motor up all the way. went to leave and thought i had trimmed it all the way down well it looked that way. not sure what happen next but got on the throttle in the inlet and almost flipped it bow over stern. that thing hauled @$$. engine was way to big for it.
Had a 25hp on a 10 foot john boat as a kid. Had to put my fat friend in the front to reduce the pounding. We lived in WW during the summer and run around in the back. Dad worked in the refinery and only came down on the weekends, so mom ran the show. She saw us flying down the cannel one day and kicked my *** and my friends. Last year (I’m 50 now) my Dad and I were down there and he told me how mom had mention to him that she took my “Power” away after he saw us rowing the boat. Stupid thing to do but fun. Today they have fines and police and insurance and whatever…