Hi, I bought a 2012 leftover SS 201 I/O with a 220hp Mercruiser with an Alpha 1 Drive and it came with a 3 blade 14.25 x 23 inch pitch aluminum prop.
According to the dealer's test technician, he tested it at 52 mpi @ 4800 WOT. However, when I got the boat and broke her in, the best I could do was 45 (GPS) MPI @ 4400rpm!! I was not only somewhat confused but disappointed. Either the technician was lying or something happened in transportation to the boat which was less likely.
I borrowed a 14 x 21 aluminum prop and was able to hit 5000 RPM and about 44MPH in rough and windy lake water while the 23 pitch could do only about 41 or 42.
I am thinking about putting a 14 x 22 inch pitch stainless steel cupped prop on and would like to get your comments, which would be welcomed.