And the results are.....

[ported0]

Fuel figures follow.

Bayliner 2655 wide beam 7.4 litre Mercruiser Bravo 2

3/4 tank fuel, full tank water, tender and outboard on the back and 3 up.

Conditions slight with wind at 10mph NW
Bottom - slimy

RPM Knots L/PH
1500 6 15
2000 7.2 23.7
2500 7.8 31.5
3300 17.5 49
3500 20 58
4000 25.1 71
4500 29 87
WOT 32 95

John

 

[aquaholic]

Not too sad all things considered then ?

 

[fluffc]

Abd converted to nautical miles per litre and nautical miles per gallon...

RPM knots Lph nm/L nmpg
1500 6 15 0.40 1.82
2000 7.2 23.7 0.30 1.38
2500 7.8 31.5 0.25 1.13
3300 17.5 49 0.36 1.62
3500 20 58 0.34 1.57
4000 25.1 71 0.35 1.61
4500 29 87 0.33 1.52
WOT 32 95 0.34 1.53

I guess that you got onto the plane between 2500 and 3300 RPM?

Interesting to observe that the fuel used per mile is the same regardless of speed above 3300 rpm.

 

[Gludy]

Expressed in Miles per litre:-
Knots MpL
7.8 - 0.24
17.5 - 0.35
20 - 0.344
25.1 - 0.35
29 - 0.33


So you use a lot more fuel going slow and fuel consumption when on the plane is almost steady regardless of the speed.

Expressing in mpg or mpl is a far better way to understand fuel consumption. /forums/images/graemlins/smile.gif

 

[ported0]

yup once onto the plane the range stayed more or less the same so just a question of how fast you want to get there /forums/images/graemlins/smile.gif

 

[fluffc]

.. or how many £ per hour you can spend on the water ...

... slower you go, more time on the water per pound, better justification of having a boat ...