I have a 1986 Searay Sundancer with a Mercruiser 350, 260HP, Alpha 1
sterndrive and boat weight of about 4700 lbs. I would be interested in the
prop size from any other owners of this size boat and engine. Specifically,
what kind of speed to do get at 3000 rpm or 3500 rpm for a given prop size.

With 2 adults, full tank of gas (70Gal) and water (30gal), I get around
19-21 mph at 3500 rpm with the outdrive and trim tabs optimized.This seems a
bit slow for this rpm. I have a paddle wheel speedometer and GPS readings
and they are close, depending on the wind.

I don't know my prop size now, but will be getting it this week, weather
permitting. Any help or suggestions would be appreciated.