How is HP measured on an outboard?

[CN Spots]

Specifically, what type of device? I don't recall having ever seen an outboard being tested for HP and I was just wondering what type of gizmo they used.

Thanks

 

[Chris1956]

Re: How is HP measured on an outboard?

I would think they use a dynamometer.

 

[DJ]

Re: How is HP measured on an outboard?

I've dealt with several dealers (advanced) that had prop shaft dyno's.

Every outboard I had tested ranked slightly over rated (prop) HP. Most about 5%, Some approaching 10%. The Japanese outboards seem to rate closer to stated HP. American OB's (Merc.) higher. None were over 10%.

 

[CN Spots]

Re: How is HP measured on an outboard?

I see. Thanks!