Re: 140 evinrude sport
Back when that engine was produced, engines came with a prop in the box. Boats were much smaller then. It would have come with a 21 pitch aluminum. If it did not work optimally on the original owner's boat, the dealer would exchange it for the correct one. Today engines don't come with props due to the wide variance in types of boats: deck boats, pontoons, fishing boats, etc. So it's really impossible to recommend one. So your prop will be by trial and error. You will want to settle on a prop that will ultimately let the engine rev to 5500-5600 at wide open throttle.