Rinker Festiva 212 propellor selection

William12

Dear all, may you please guide me from where to start as currently my boat is running a 21 inch pitch propellor driven by a 4.3 L v6 mercruiser (2 barrel carb) with alpha 1 gen 2 leg. The issue is that I am heaving a lot of cavitation and over revving of the engine while not gaining any speed at all. Max speed reached 32mph at 5200rpm. Your help is appreciated, best regards, Will

Pat310

Welcome to the forum Will. I would first check the prop hub to make sure it is not the problem. Had a similar boat and ran it with 17, 19 and 21 in props and never had it lose that much speed.   
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