"Tim" wrote in message
oups.com...
of course, if you backed it down to about 3000 rpm the speed wouldn't
be much different, and the savings in fuel can be a better edge even
yet.

I've run my little Chris Craft with a 4 banger alpha 1 at 3000 and it
does rather well. at 3500 the fuel consumption goes up with little
speed change, and 4000 rpm the fuel really drops and doesn't gain
hardly much speed over the 3500.

I suppose you might say that the percentage of speed vs. consumption
really drops out of your favor the higher rpm you go.

3000 rpms puts me below cruising speed and I start to de-plane. That's one
thing that irritates me about a mono-hull compared to the cats I'm drooling
over. With my monohull boat, I can only go 3 speeds, slow (which feels like
a one armed swimmer), cruising speed, or faster. The cat I will have
someday should allow me to go 15 mph or 30 mph without significant
differences in the ride or handling.

-Greg