Need help: Mercruiser Alpha Gen II or Bravo II ??

Discussion in 'Propulsion' started by Bruce P, Dec 12, 2010.

  1. Bruce P
    Joined: Oct 2010
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    Location: Alaska

    Bruce P Junior Member

    I am repowering my 32' cruiser (planing hull) with twin Mercruiser 5.0 MPI 260hp. Wet it will displace 12,000 to 14,000 depending on the number of people, fuel, etc. All decisions have been made except for the drive leg. I have the option of putting on new Alpha or Bravo II drives, where the Bravo option will cost about $3,000 more (total for both). Alpha is less money, less drag, weighs 120 pounds (total) less, and is limited to a 15" diameter prop. The Bravo II will swing a 20" prop. My mail goal is fuel economy and handling at a medium cruise speed.

    What would you choose? I have asked a number mechanics and experts and have received 3 votes for the Alpha and 3 for the Bravo. I need to make this decision quickly and any replies would be greatly appreciated!
  2. CDK
    Joined: Aug 2007
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    CDK retired engineer

    Cheap is definitely wrong here. With 260 hp the Alpha is at its limits and will not live long because of wear and material fatigue. It does have less drag but that advantage is more than nullified by the slip of the smaller prop.
  3. powerabout
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    powerabout Senior Member

    Bravo II no question and dont forget to thank us after the first year, the second year and so on.
    1 person likes this.
  4. Bruce P
    Joined: Oct 2010
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    Bruce P Junior Member

    Thankyou for the response! That helps a lot. Anyone else before I pull the trigger?

  5. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    On a heavier boat, the Bravo will do better. It has better low end and better fuel economy in the mid range. Also, it is stronger.
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