50 hp "then and now"

[GaryAK]

I have a 1970 Harvey pacific bar dory. Recommended power back then was 50-70 hp. I was talking to a salesman about motors today and he said that back when the boat was manufactured that the hp rating was taken from the power head and today they assessed at the prop. He also said that a modern 50 hp would be about equivalent to a 70 hp from the 1970's. Is this correct info? I'd appreciate some opinions.

 

[JB]

Re: 50 hp "then and now"

Howdy, Gary.

I don't agree with the sales dude. It is true that most outboards were rated at the flywheel prior to the mid '80s, but here is no way that the drive train used up 20HP; more like 4 or 5.

That would mean that a modern 50HP would have about as much at the prop as a 55HP from the mid 70s. Comparing them under load it is unlikely that you would notice a difference.

We don't know what the prop HP was of a 70s 50HP and we don't know the flywheel HP of a late model 50.

I have used JohnnyRude 70s from the '70s and from the '90s and I couldn't tell any power difference.

 

[GaryAK]

Re: 50 hp "then and now"

Thanks, JB. It didn't seem right to me, either, but I didn't argue the point. I did have some serious wishful thinking going on, though....for a little while, anyway!