Re: Johnson 35hp vs 40/48hp
Torque usually relates closely to displacement. Since the 40/48 are 747 CC, they would have considerably more torque. The three cylinder would obviously be much smoother, especially at slower speeds. Fuel consumption, horsepower, and displacement also follow each other closely. A smaller displacement engine will typically burn less fuel than a larger one -- all other things being equal. Since you aren't comparing apples to apples in this case, you really need to look at the application. The 35 for example may be just marginal for the boat you intend to put it on. It would therefore have to run wide open all the time just stay on plane. A 40/48 on the same boat on the other hand would likely pop the boat on plane quickly, haul a bigger load, and loaf at cruise while getting equal or better economy because it simply is not working hard.