# So where is a jet outboard the most efficient?



## JL8Jeff (Jun 6, 2014)

I used to run my old Hobie Power Skiff with the 40 hp Johnson prop in a sweet spot that seemed somewhere around half throttle. I'm still getting used to the Merc jet and i'm really running it where it seems to be the smoothest/quietest while going upstream. I'm obviously going through more gas than the prop did, but it made me wonder if there is different engine speed for peak efficiency with the jet. Do jets run more efficient at a higher rpm?


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## hotshotinn (Jun 6, 2014)

my motor does best as far as gas useage at 3/4 throttle.I have a 40/30 Yamaha four stroke.Same for my big motor as well,225EFI mercury on bass boat


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## dhoganjr (Jun 8, 2014)

Jets seem to vary according to hp. They should be most efficient between 2/3 and 3/4 throttle. IMO it should be about where you can keep the boat on plane and not push water. Just like with props they all vary between boats, engines, weight placement, etc. *More so on the weight placement.* 

With more weight it requires more hp to stay on plane making them even less efficient. So it makes it even harder to determine where they are most efficient.

With my boat going from the 115/80 to the 250/175 I use about the same amount of fuel or less if I stay out of it. I can run 1/2 throttle with what used to take 3/4 or more. Mine seems to be most efficient at about 4000 rpm's which pushes it to 35mph. And the 250 doesn't care what kind of weight I carry. It took full throttle to run 35 with the 115 and that left nothing in reserve for steering.


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## Wood_Duck (Jun 24, 2014)

I run my 30/25 at around 3/4 simply because its less stress to the engine and honestly from there to WOT I only pick up a couple mph


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