[templar]

2. I also have some trouble believing that 1700 rpm is the diesel engine's optimum speed -- it sounds too low.

Probably a 'stationary engine' type of engine that is designed to run at a specific speed only. Load increases injector volume to maintain a constant speed no matter what the power draw. Some of those China Diesel generators I've seen seem to run ar pretty low speeds. That's why they seem to run for ever, I immagine.

[expatpat]

Yeah, I figured it was a constant-speed engine, but am surprised that that low speed is the optimum for efficiency. It would certainly be good for long life.

[CommandoFrank]

Bingo... the diesel is famous for high torgue at low RPM. Low RPM equals long engine life...

I love my Ram Diesel...