Cost of fuel...

[lakewinnie]

Originally Posted by Dave R

Not many boats on the lake are going to achieve 2gph at 8 knots (though pontoons might be able to, I don't know much about them). That's 50' single (small) diesel trawler territory. A typical lake boat that can actually burn 30 GPH (that's around 400 propshaft HP for gas) is going to maybe see 4 knots at 2GPH.

A few years ago, when gas was around 4 bucks a gallon on the street, we often saw people cruising around at 7 to 12 knots in <30' v-hull boats. That's literally the worst possible speed range for MPG in boats like that. Either run at idle or cleanly on plane at around 50-60% power (or faster). My last boat, a 25' deep V with a Bravo 3 I/O got 2 MPG at 50 MPH (43 knots and WOT). It got 1.4 MPG at 10 MPH (8.6 knots). At around 30MPH, it got around 2.6 MPG on average.

I'm not sure how this equates to MPG, but I get around 5 GPH at 30 MPH in my 24 foot Four Winns bowrider with the 5.3 liter Volvo Penta. That seems to be the sweet spot.