For some reason outboard manufacturers don't put out the graphs which show RPM, Torque, Fuel consumption and HP, as do the diesel and gas inboard engine builders.
I have never been successful in finding these, although there are many published for the other engines.
What you can find is the "performance" tests--where the RPM vs fuel burn is given--but usually these are with very light boats, and don't reflect the real world fuel burn.
For example the Suzuki 115 on a sea chaser 18 with total weight somewhere near 1700 lbs.
RPM spreed gal/hr M/gal
3000 8.3 3.40 2.40
4000 26.2 4.80 5.50
Notice how the boat jumps from 8.3 to 26 mph to get on a plane. The C Dories have much less of a transition, and plane at a lower speed.
This is just one example--http://www.suzukimarine.com/boat_builders/boat_tests/
There are a number of other boats with the 115, but nothing tested really like the C Dory. This may well show us why no curves. The boats act so much differently--depending on hull design, weight, props etc....
I have an 18 foot Century with 115 Yahama total weight close to 2000 lbs, and I have to get it up to 3500 RPM to get it on a plane--and it falls off the plane as I drop much below the 3500 level. As it breaks out of the semidisplacement mode, it goes from 9 mph to 15 mph, and will not run inbetween the two speeds.
I have never been successful in finding these, although there are many published for the other engines.
What you can find is the "performance" tests--where the RPM vs fuel burn is given--but usually these are with very light boats, and don't reflect the real world fuel burn.
For example the Suzuki 115 on a sea chaser 18 with total weight somewhere near 1700 lbs.
RPM spreed gal/hr M/gal
3000 8.3 3.40 2.40
4000 26.2 4.80 5.50
Notice how the boat jumps from 8.3 to 26 mph to get on a plane. The C Dories have much less of a transition, and plane at a lower speed.
This is just one example--http://www.suzukimarine.com/boat_builders/boat_tests/
There are a number of other boats with the 115, but nothing tested really like the C Dory. This may well show us why no curves. The boats act so much differently--depending on hull design, weight, props etc....
I have an 18 foot Century with 115 Yahama total weight close to 2000 lbs, and I have to get it up to 3500 RPM to get it on a plane--and it falls off the plane as I drop much below the 3500 level. As it breaks out of the semidisplacement mode, it goes from 9 mph to 15 mph, and will not run inbetween the two speeds.