Re: Best RPM for Maximum MPG?
Google or Yahoo "Northstar 210" or "Navman 2100". They are identical units since Northstar acquired Navman. These units work well. I have one.
I have a Standard Horizon fuel flow meter that was in that same price range and is very similar/identical to the Navman unit. At the time I bought it, I kind of assumed they were re-badged identical units. I believe they even used the same sending unit.
I'm wondering how your luck has been with the Northstar / Navman unit? Unfortunately, I've had nothing but problems with my SH and am about to abandon it. In fact, I believe SH has discontiued their FF meters. I've had the sender replaced once (defective/cracked original unit), but have had the gauge itself replaced twice and now have the same problem a third time - total fogging and malfunctioning of the display.
Anyway, when it worked, I was happy to have the flow meter and recommend them if they can be reliable. I liked seeing the GPH display, and set it up to use as a fuel remaining gauge also, and it was VERY accurate.
But, in order to determine the most efficient speed across the water you need to calculage MPG which involves the flow meter and an accurate speedometer (i.e. GPS) and then calculate maximum MPG. I found that my maximum MPG wasn't the same RPMs as maximum GPH. I could go further at a higher GPH because I was going faster. Maximizing distance/gallon was my goal.
There are GPS units that hook in with flow meters to calculate MPG on the fly.