Wayne.B wrote:
Doug, what kind of boat/engines?

36' hard chine tugboat with a Ford Lehman 135SP.

http://community.webshots.com/photo/...76569411zLxjAQ

We have a four blade prop which I suspect has a bit too much pitch,
clean & light the engine will not get up to rated RPMs.

http://community.webshots.com/photo/...73346078zEdpFX

1600 rpm (which is a little below recommended cruise) gives us about
7.25 knots average and is relatively quiet & efficient. Other cruises
we've been in more of a hurry and burned 2 ~ 2.2 gph.

Fair Skies
Doug King