Didn't they have something done to the prop in Australia when they were
hauled? I don't believe that you achieve efficiency by over-propping, but
I'm willing to learn. I just finished eliminating over-propping on my
Willard 40 and she clearly runs easier.

Ron Rogers

----- Original Message -----
From: "Willy Loyd" cfeinc@telus.net

| >Idlewild is powered by a 55-hp Kubota which, Ben Gray told me in
| >Vancouver, generally ran at 15-20 hp sipping just a tad more than 1
| >gph.
|
| >For greatest efficiency, you want to be skinny as well modestly-powered.
|
| >--Georgs
|
|
| The boys also added they over propped, using an over pitched four bladed
| prop. Compared to the best match three blade they had. Working the power
| hard at low RPM. Experience from Bens earlier test runs, he changed the
prop
| for there intended use if I remember correctly.

Engineering theory generally would say that producing the same horsepower at
a lower RPM will reduce fuel consumption, therefore overproping i.e. more
distance per revolution will improve fuel consumption, maybe to the extent
of a few percent.

This is still a bad idea because it reduces the ability of the motor to
produce proper RPM for maximum horsepower resulting in reduced top speed,
and increased risk of damaging the motor at the maximum speed the engine
will drive the boat.

John Harris