Speaking for carbeurated outboards (I'm sure this translates to others) the
best fuel economy seems to be when the throttle is far enough forward to hit
max-advance, but no so far forward that the carb throttle bodies have
significantly opened. My experience is about 4000 RPM - give or take a
hundred or two.

-W

"RB" wrote in message
...
I've had several boats with big single and twin o/bs in the past. I
remember most as having a "sweet spot", which was just down from wide open
throttle (WOT). Many of you are probably familiar with a sweet spot.
Cars
and trucks have been known to have them. Seems like going to WOT can eke
out a little more speed, but things are straining, coming back down a
little
seems to let everything harmonize and get in the groove, and run more
smoothly.

The question I have is: assuming a boat with o/b has a sweet spot, is my
fuel consumption more efficient at the sweet spot than wide open? Sounds
like it would be -- a little bit---as you come back on the throttle to get
to the sweet spot. Or, is it that there's no real reason to run at the
sweet spot, other than it "feels right", and good?

Just curious