For my use 80 would be the minimum. Your use may require less.

My current boat is 16' FRP and it's powered with a 115 hp OB.

I'm not familiar with a Sunray. If it is a lightweight skiff it may do well
with only 80 hp. However, in my experience FRP boats from the seventies
tended to be heavily built.

Butch
"Chris" wrote in message
...
I suppose my question is simply this: based on your knowledge of what it
takes to properly push a boat, here's a model, now what do you think the
minimum horsepower required to push this would be?

1975 15'5 Sunray (Fiberglass boat)

50hp?
60hp?
70hp?
80hp (this is what it currently has)



"Chris" wrote in message
. ..
hi there,

I've been tinkering with a 1972 80hp merc that I got some time ago that
started, but has since failed to. It appears there may be a problem in
either the switch, and / or coil. Based on the prices of these old parts
it could be pretty pricey if they both need replacing (which I wouldn't
doubt). My alternative to just not fixing it, is to get another motor
that is newer and in good working condition for a bit more. I'm keeping
my eye out on those prices too, but have an important question to
consider... Could I use a smaller motor?

This old 80hp has powered a 15.5 ft fiberglass boat. But could a newer
motor of a smaller HP do an equal or pretty good job? Perhaps a 40hp of
a newer vintage?

Has anyone had experience changing motor sizes?

Chris