I just bought a 2015 mercury 25hp 4stroke 1.92 gear ratio. It has a beat up Merc 9.75 x 9.50 AL prop that pushes the boat well. It runs 26-28 mph at 5700 rpms. I am happy with the performance but I think I might can get a touch more out of it. I need a new prop because this one is pretty banged...