the fastest omc 56 cu in on the day was 56mph...
The first boat on the radar in that video ran max speed of 56mph that was kevin harolsons hotted up 56cu in evinrude 1990/2 bridgeport.
running a 22 raker prop on his weldbuilt.
20 onch midsection on jackplate 2.42 gear ratio and around 6700rpm top end. that's a slip of just around 2%.
the engine was rebuilt with new pistons and rings, 30 thou over bore, shaved head 40 thou, drilled exhaust. ported and balanced rods and crank.
it maxed out at 56mph that's good. but nothing like 70mph that he tried to claim on strictly .
fastest boat there was 69 running with a Yamaha 90 powerhead on a 70 mid with small gearbox and fully modded powerhead..
most of the boats are mid to high 40mph in the 60 to 70hp bracket.
if you go on a the next vid to that one youl hear the classes they run.
in the over 45mph bracket class only 4 boats there. kevin won a 3rd or 4th
most of the merc 60hp and omc 60/70 hp run mid 40's on those boats, only ones to run 60mph are using the NOS.
here is kevins 56 cu in gearbox and mid after camo paint
here it is before the camo look