Engine HP verses RPM

[honda lee]

I am trying to match hp with rpm. If a engine is rated at 24 hp at 1000 rpm and you ran it at 750 rpm would you make 18 hp?

[dieselgman]

It is hard to say for certain... The graph of those power curves are not necessarily linear, it depends on how the manufacturer calibrated the rating and which engine type you are referring to. Most diesel engines have a power curve that flattens out dramatically at higher rpms.

That said, if you are well within the normal power band range of the engine you could use your assumption as a general guide. I don't think you will find too many modern engines with a 750 rpm power rating.

dieselgman

[richardhula]

I am trying to match hp with rpm. If a engine is rated at 24 hp at 1000 rpm and you ran it at 750 rpm would you make 18 hp?

Its a straight line graph for Listers CS cousins, the more sophisticated (relative term) JP series. Can't imagine a plain CS or derivative would be much different at the top end at least.

[honda lee]

Lets see it!

[honda lee]

I'm thinking I will go with the 4.2" that should put me at 760 rpms if I figured it right. The 5" would put me. At 900 and that seems a little fast and at 760 it should produce all the power I need. Unless the power drops more than 25%