Comfortable cruising speed

"been working on my 1988 4 win

"been working on my 1988 4 winns 205 sundowner, 260 mercruiser,,,wondering what should be a comfortabie cruising speed....and what she should run wot.....right now having rebuilt out drive presure tested ..but also looks like i am gonna need a new gimbal rim...or steering arm/nut,,,,fairly new at the i/o wrenching...."

An close estimate of WOT speed

An close estimate of WOT speed in MPH is easily figured by taking the square root of shaft hp divided by boat weight times 190. This allows for about 15% prop slip which is about average for light V bottom boats. A good cruising speed would be at about 3500 RPM which should give you about 65% of your max WOT speed. The weight you should use is empty boat weight + gas + gear + driver.
Note that to go faster takes the square of the speed increase in additional power. Thus to go 50% faster takes 2.25 times as much power. This is why even boats with 1000 hp or more still only go about 100 mph.
Rod