BoatBanter.com - View Single Post - The Right Size Outboard Gas Engine for a 18-ft Boat?

wrote:
: I would like to know the proper size outboard gas engine that I should
: put on a 18-ft aluminum semi-V/deep-V boat.

: According to Tracker web site, they stated that the max HP for their
: 16-ft deep-V aluminum boat is 40HP. I would assume that the max HP of a
: similar 18-ft boat "may" be around 50HP (?)

50 HP seems very low for an 18 Ft. boat. I'd think something closer to 75 to
100 HP would be more reasonable.

In the "old days" of Bayliner, for example, they put very underpowered I/O's
in their boats (4 Cylinder engines in 18 Ft. boats for example). The
end result is that most people ran them flat out (full throttle) to obtain
sufficient speed. With a larger engine, they would have actually gotten
better fuel economy because the engine was running in a more economical
RPM range.

As others have mentioned, new boats are now required to have a USCG plate
on them specifying maximum load and power. I'd select an engine toward the
high end of the HP range on that plate.

b.