Boat engines and WOT

[Cujet]

Bob and I did some interesting fuel flow/MPH/MPG calculations on his 4 cylinder, 2 stroke 115HP Mercury powered bass boat. The results surprised us so much we did the tests multiple times.

In this case, all the conventional wisdom was worthless. The boat was clearly most efficient at very near top speed. Going slowly in this (admittedly underpowered) bass boat was simply wasting fuel.

Going just fast enough to achieve a steady plane was way off the efficiency curve. Going 42MPH was best. Top speed was around 44.

 

[fdcg27]

You could always buy a real boat, one with a mast or masts and sails.
Only time you'll ever need to run an engine is as a convenience in getting the boat out of its dock and then back in.
Sailboats work great on the lakes.
There is nothing nearly as relaxing in any boat as setting up a nice tack and then cruising on it.
A keel boat is also safer and more stable in rough water than any power boat, although you won't be trailering one.
Ask me how I know.

 

[hattaresguy]

I run the motor/motors all the time when I cruise on sailboats. You have to make time, if your not doing at least 6 knots a 1k mile passage is well...going to take forever.

Plus most of the time the wind is coming from exactly the way you need to go. Beating up 500 miles isn't my idea of fun.

The sailboat I cruise on a lot is a cat and the Yanmar diesels have over 1500 hours on them in a couple of years.

Also at night, we reduce sail unless were racing because fighting the sails at 3am in a micro burst is dangerous. Its very easy to get hurt, lost overboard, or break rigging if you don't know what your doing.

 

[fdcg27]

Amen to everything you've written.
The largest sailboat I've run is a single hull 26' sloop, so I have a little different frame of reference.
We used the boat mainly for pleasant cruises on Lake Erie, and you aren't going to go very far on the lake.
I agree that running close to the wind on a long run would get pretty tiresome and having to manage the sails through the night might also be a bit of a drag, espcially if you run into bad weather.
Still, there are those who've done incredible distances under sail in small boats.

 

[Too_many_Cars]

I have a few problems. 1. Never enough HP. 2. Never enough fuel. 3. Never ever enough money to spend on fuel. 4. And never ever ever enough SPEED!
We put the fastech in last weekend. Ran very well for a 14 year old girl. 454 mags with a little work. Only 245 hours on her. We purchased the formula new in 2000. Don't ever run a cost pet hour index. It will not make you happy. I do love 5600 rpm's just a touch out of sync. We do run on Lake Erie. 3 to 4 foot chop was fun. But...... I was younger then

Joe