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  1. #1

    Got a new impeller, needs tweaking. Pitching advice, please!

    Boat: '07 Speedster 150 215HP (minor mods in sig)
    Altitude: 5200-6200' asl
    Impeller: Skat Track Swirl 3-blade 12/15
    Performance priority: Hole-shot! Love "torque" and Colorado has 40mph lake speed limits

    Results with the new impeller:

    - Hole-shot (from dead stop): revs peg at 8180rpms for about 1-2 seconds
    - Top-end: rpms cannot get bast around 7660-7680rpms (around 55mph on speedo)

    So, as a noob to pitching, I don't know where the 12/15 should go from here. Clearly the top-end can and should be tweaked, but should the hole-shot be tweaked at all? I don't want to do anything at all to take away from the hole-shot. Thanks in advance.


  2. #2
    speedskixp's Avatar
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    Ditch the bov before you do any tweaking.
    Generaly an over pitched prop will spin less out of the hole but will also majorly kill acceleration.

  3. #3
    Sounds like cavitation outa the hole.

  4. #4
    speedskixp's Avatar
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    Quote Originally Posted by VaRedneck View Post
    Sounds like cavitation outa the hole.
    Keep in mind it's a boat. Probably gunna spin some out of the hole no matter what.

  5. #5
    Quote Originally Posted by speedskixp View Post
    Ditch the bov before you do any tweaking.
    Generaly an over pitched prop will spin less out of the hole but will also majorly kill acceleration.
    Previous owner did the BOV. Why would I want to ditch it?

  6. #6
    Quote Originally Posted by speedskixp View Post
    Keep in mind it's a boat. Probably gunna spin some out of the hole no matter what.
    Yep, it's a boat for sure. Hole-shot is pretty damn good, really. Not too far behind my '03 GTX SC 185hp at all... near comparable. Guess I should ask on the boat forum if anyone with any setup can get a hole-shot to grab and go without pegging the rev limiter. Mine pegs it, but only for a second.. definitely not 2 seconds.

  7. #7
    speedskixp's Avatar
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    Quote Originally Posted by Guy on the water View Post
    Previous owner did the BOV. Why would I want to ditch it?
    Because they tend to leak and could be costing you some rpms.

  8. #8
    As far as the BOV goes, can I just plug the elbow hose (from SC) where the BOV is to test if rpms come up?

    Assuming the BOV is not leaking and current pitching is 12/15, where would the pitch need to go to take my current top rpms of ~7650 closer to 8100? Would doing so hurt hole-shot at all?

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