81 Catalina 38 '''' Sparkman Stevens
That is true about the props. One question to the original poster, was I to read that that is an Atomic 4 gasoline engine?
Either way a 25HP is not really undersized, just a bit on the lower side for todays standards. But if you want to get the most "Oomph" out of your engine the prop to go with IMHO is the Autoprop. The reason is that the Autoprop is self-pitching in theory always finding the correct pitch depending on conditions and boat speed. I know of a lot of C36 owners that put the Autoprop on older C36''s that had the 25XP engine and most say they saw a noticeable increase in boat speed at all engine RPM''s. Not a cheap alternative (about $2k+) unless you might be able to find one used. But much cheaper that re-powering your boat!