BoatBanter.com - View Single Post

Martin Baxter

wrote:

The easiest way would be to find out much current the thing uses.

I*E=P, assume about 90% effeciency, so HP= (P*0.9)/746

If you want that in simpler terms HP= ((volts x amps)*0.9)/746

Cheers
Marty

Don't leave out the fact that the electric trolling motor power is
produced directly at the prop. There is significant power loss in a
gas outboard between where it is produced and the prop that does the
work.

Hmm, I don't really know, but I don't think the losses should be all
that big, one little water pump to turn, on set of crown and pinion
gears. Intuitively I don't think you'd lose more than 15%..

I'll bet that most outboard manufactures measure output of just the
head, no shaft, no water pump.

Cheers
Marty

------------ And now a word from our sponsor ------------------
For a quality usenet news server, try DNEWS, easy to install,
fast, efficient and reliable. For home servers or carrier class
installations with millions of users it will allow you to grow!
---- See http://netwinsite.com/sponsor/sponsor_dnews.htm ----