Got an 89 Sea Ray 220 Sundancer, Mercruiser 5.7L, ALpha 1 Gen 1 outdrive with 14.5x17 aluminum prop. Engine was turning only 3900 rpm @wot, sooo I went down to 15x15 ss prop (Quicksilver). Rpm's came up to 4700 + rpms. Here's where it gets interesting. I now go up to 14x17 ss prop (Stilleto) to...