Chuck,

Where did you get your fuel consumption numbers? They are a bit on the
low side in my experience. The normal rule of thumb for gas engines,
which I've found to be pretty close, is 1 gph for every 10 hp. At 3400
RPM most engines, properly propped for the boat, will run at about 50%
of maximum rated power. That would put the 350MPI at 15 gph and the
496 HO at 21 or 22. I have neighbors with both engines and that's in
the ballpark for what they are seeing. My old 350 4bbl rated at 260 hp
has always burned right around 13 gph at 3400 cruise.

wrote:
Chuck,

Where did you get your fuel consumption numbers? They are a bit on the
low side in my experience. The normal rule of thumb for gas engines,
which I've found to be pretty close, is 1 gph for every 10 hp. At 3400
RPM most engines, properly propped for the boat, will run at about 50%
of maximum rated power. That would put the 350MPI at 15 gph and the
496 HO at 21 or 22. I have neighbors with both engines and that's in
the ballpark for what they are seeing. My old 350 4bbl rated at 260 hp
has always burned right around 13 gph at 3400 cruise.

The carbed 350 in the Mercruiser chart is a 2 bbl, not a 4 bbl, and the
9 gph is at 3000 RPM vs.your observations at 3400.... 9.0 gph for a 2
bbl operating at 3000 vs. 13 gph for a 4 bbl operating at 3400 probably
represents as much difference between the two figures as would be
believable- but I don't think the difference defies credibility.

Other differences between the "dock talk" numbers and the Mercruiser
figures may (possibly) be due to MPI or other advances in engine
technology, may be influenced by the fact that the Mercruisers tested
by Mercury Marine will typically be perfectly in tune, and results from
controlled tests will undoubtedly vary from horseback estimates made by
boat owners. Most boat owners may not be actually running at a fixed
RPM for an extended period of time and many are probably not using a
fuel flow meter.

Mercruiser is a Brunswick product, and the fuel consuption data is from
a sales borchure for another Brunswick division.

Can you accept attachments at your hotmail address? If so, I'll scan
the page and email it to you.

Can you accept attachments at your hotmail address? If so, I'll scan
the page and email it to you.

Yes, attachments are no problem.

My 350 burns about 9 gph at 3000 RPMs also. Probably it is running on
only 2 bbls at that speed.

wrote in message
oups.com...
Chuck,

Where did you get your fuel consumption numbers? They are a bit on the
low side in my experience. The normal rule of thumb for gas engines,
which I've found to be pretty close, is 1 gph for every 10 hp. At 3400
RPM most engines, properly propped for the boat, will run at about 50%
of maximum rated power. That would put the 350MPI at 15 gph and the
496 HO at 21 or 22. I have neighbors with both engines and that's in
the ballpark for what they are seeing. My old 350 4bbl rated at 260 hp
has always burned right around 13 gph at 3400 cruise.


Wayne,

Since I gotcha....

Do you have the inflatable/dingey setup on your boat on the starboard side
of the aft cabin?
Mrs.E. has me on a mission to find one that fits the existing holder
(davits?) .... I don't know what you call it.
She wants something with a small outboard. Any recommendations?

RCE

Yes, our dinghy is on the starboard side of the aft cabin. It is an 11
ft Caribe RIB with a 15 hp Merc which rides and performs well for a
boat of that size. It would be too much weight without a hoist
however. We use our mast and boom as a cargo crane but have extra
reinforcing stays on the mast, in addition to an electric hoisting
winch, and multi part block and tackle on the boom lift.

Unless you have an electric or hydraulic hoist, you really need to
stick with something that is light and easy to handle. A small, soft
bottom Avon with something like a 3 hp OB would fit that description
but not perform particularly well except for short harbor hops.