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Is this all she's got?

Discussion in 'V-Drives' started by stupidbaker57, Aug 26, 2013.

  1. stupidbaker57

    stupidbaker57 Well-Known Member

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    Well I finally had a calm day and a chance to get the flatty to fly. I got 65.1 MPH at 4500 RPM's. I'm running a 12 degree shaft with 15 gears spinning a 12/16 3 blade. When I was running a 12/14 3 blader, I got 50 at 5000. Is it possible to get more out of her? Change prop, cut prop down, decrease pitch, etc? I'm not looking for a speed record or anything,,,,,,,just want to beat my son's wacker boat (72MPH).
     
  2. stupidbaker57

    stupidbaker57 Well-Known Member

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    I took my nimbral 12/14 prop to the shop and was told that it had a bent ear. I had it pitched to 15, cupped, sharpened polished and balanced all for $75. With this prop I get 61 MPH at 4700 RPM's. The engine is a 383 Chysler 400 HP a 12 degree shaft and 15 gears.
     
  3. vdcruiser

    vdcruiser Well-Known Member

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    I've found that 12" dia is a little big for a flat bottom. How is the boat running at speed, flat and stuck to the water or loose and hopping some. I had a couple of Howard flats and the way I got the best speed was to let them hop,(porpoise), quite a bit. They also had 10 deg shaft angles.
     
  4. stupidbaker57

    stupidbaker57 Well-Known Member

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    Yea,,,,,she does hop a bit at the end,,,,but nothing too bad that can't be controlled. Another couple of runs and then put it away 'till spring while I work on my next "toy".
     

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