help prop size!

Discussion in 'Bubba's Outboards' started by molly, Mar 11, 2009.

  1. molly

    molly New Member

    Messages:
    13
    State:
    mississippi
    I have a 2007 yamaha f90 and am thinking about changing from an aluminum prop 13x19 to a 13x21 stainless. The boat is a 1860 g3. Looking to pick up a little more speed. Any suggestions would be appreciated!
     
  2. roadkill636

    roadkill636 New Member

    Messages:
    551
    State:
    warrenton misso
    It all depends upon what rpms your motor is turning at WOT right now, and what the max rpm the motor is rated for
    its VERY easy to over prop an engine and loose rpms and speed
     

  3. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    What RPM's are you turning at WOT now? If you are in your power band then That is where I would Stay. If it was mine I would take my existing prop and have a little more cup added to it to get a better bite.