Horse Power rating change over

[ctgmopar]

Does anyone know what year Evinrude/Johnson changed how they rate horsepower? I know the HP used to be rated at the base of the powerhead. It was changed to being rated at the prop.....What year? Thanks, Chris

 

[05GlastronSX]

Re: Horse Power rating change over

some time in the late 80s all manufacturers switched over. I believe it was mandated in 1988.

 

[JB]

Re: Horse Power rating change over

They didn't do them all at the same time, but 1985 is when most of them were re-rated.

 

[Wover98]

Re: Horse Power rating change over

For the lay-men just how did this affect things? Was an older 25 now rated 15? or vice versa? (Numbers are just numbers, I know they are not precice)
Just what difference are we talking about?

While we are at it, what about the newer 4 strokes? The 25 4 stroke looks like a monster, with tilt and trim and such compared to my old mid 70's 25 2 stroke. Is speed and power about the same? or is the extra size inclusive with lots of weight and less performance? I know....noob questions but that is what I am I guess.

Thanks
Will

 

[ctgmopar]

Re: Horse Power rating change over

Thanks for the answers everyone. I was originally going to get a bigger engine for my bowrider, but the 70hp I am looking at is new enough that I should have a 10hp gain from the 1977 70 evinrude I have now.

As for the question about what the difference is.....the older engines were rated at the flywheel so by the time you get to the prop, you aren't getting 70hp anymore. Now, everything is rated at the prop, so you get exactly what you expect at the prop.....for instance an old 70hp could really be a 60hp by today's standards. A new 70hp, actually has 70hp at the prop. Hope this is explained well enough.

Chris