RickB
Guru
- Joined
- Oct 20, 2007
- Messages
- 3,804
- Vessel Make
- CHB 48 Zodiac YL 4.2
...60 HP from a 150-300 P engine is not efficient , even with a modern electronic injection engine.
Using a Cummins 6BT5.9-M as an example, at full rated power of 210HP its BSFC (pounds of fuel burned to produce one hp for one hour) is 0.397.
At a moderate output of 120HP it will burn the same amount to produce one horsepower ... 0.397 pounds.
If you pull the throttle back to 60HP, that engine will burn 0.385 pounds of fuel to produce each horsepower.
It is more fuel efficient at 60HP than at its rated maximum power output and a moderate "cruising" power.
While that particular BSFC relationship may not apply to every engine, in every installation, it shows very clearly that the statement you keep making about "low efficiency" at less than some arbitrary high power output is incorrect. It is misleading, and it is based on docktalk and rumor.