In this day of outrageous gas prices and price gouging by "The Man", I was hoping one of our resident tech-heads could answer:

I have a 115 2-stroke Yammie, do I get the best gas efficiency at full throttle or at 1/2 or 3/4 throttle?

This should be interesting....

I may not be 100% correct on this but I have been told that you get the best mileage at half throttle. I think it has more to do with the RPMS

The more boat you get out of the water the less drag you have. When this happens you get better fuel consumption. So it depends on your boat, HP of the engine, &  pitch of your prop. Each rig will be different.

Yamaha has a pretty cool tool on their site that shows test results on various boats and motors.  Check it out:

http://www.yamaha-motor.com/products/otb/perfbull/

Includes GPH (Gallons Per Hour) measurements at various RPMs.

I was just looking at a bunch of boat tests. Most of the boats that will run mid to low 50's are best at 30 to 33 mph.

Just a side note but I looked at a report on a 65 foot Hatteras. Now of course I'm sure if you own one of these, gas prices wouldnt bother you. This boat at 1000 rpm's will run 12.6 mph and burn 19.8 gph. But at 1250 rpm's you pick up 3 mph and it burns 40.2 gph. 2350 rpm's 36.4 mph it burns a cool 146 gph!

I wanted to add if you go to Boat trader and look on the left you will see boat test. Check it out, it is pretty interesting on the gph on most of these boats.