Page 3 of 3
Posted: Sat Dec 17, 2005 1:38 pm
by James B
Catigale wrote: that is impressive, never realised my 50 sucked as much fuel relatively speaking...
Speaking of fuel economy, what is the best RPM for the best MPG? and about what would that MPG be? Mine is a Honda 50.
Posted: Sat Dec 17, 2005 2:03 pm
by Moe
With a displacement hull, the slower the rpm and thus boat speed, the better, and speed is limited to displacement speed. With semi-displacement hulls, i.e. Nordic Tugs, etc. that can travel faster than hull speed, consumption skyrockets past hull speed, but at least it's possible.
With a planing hull, there's a range between displacement speed and rolling over on plane, where mpg drops severely, then goes back up to where mpg is about as good as below displacement speed. I don't believe a Mac with 50HP will ever reach that point, and best mileage will occur below 6.4 knots/7.4 mph.
Posted: Sat Dec 17, 2005 5:29 pm
by James B
Thanks Moe, would you make a guess as to the miles per gallon at the 7.4 MPH you mentioned. I'm still waiting to take my first trip on the 26X and wondering how much fuel I would need if we could not sail.
Posted: Sat Dec 17, 2005 5:34 pm
by Moe
I believe you can expect close to 4 mpg with the Honda 50, but I'd only plan on 3.5 until I knew better. For going offshore, it's best to plan on 1/3 of the fuel for going out and trolling, 1/3 getting back, and 1/3 reserve. I personally have seen fuel consumption double coming back in heavy seas.