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  #27  
Old 05-01-2009, 09:42 PM
lost2a6 lost2a6 is offline
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Join Date: May 2003
Location: Hurley, Mississippi
Posts: 386
Default Re: Porpoising Seavette

A little up date, Brett at BBlades sent me a couple of test propellers. He sent me the Mirage plus 21 pitch and a Bravo 1 22 pitch 4 blade.

Here are the results with the Mirage plus: 3000 RPM=30 MPH, 3500 RPM=40.5-41 MPH, WOT=5200 RPM @ 64.7 MPH with drastic porpoising. Even at 30 MPH with the drive all the way down it still wanted to porpoise.

Next I switched to the Bravo 1, those results are: 2800 RPM=30MPH, 3500RPM=42.5-43MPH, and WOT=5200RPM @ 63.2MPH with not near as much porpoising. I can even cruise @ 30MPH and trim the drive up some and it doesn't porpoise. Even though I lost a little MPH on top end with the Bravo1 it is by far the best all around prop for my boat. So what Brent wants to do is to Lab finish a 24 pitch Bravo1. He said that I should get more MPH out of it than the Mirage plus and that I should see 66-67 MPH. I told him to get after it.
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Steve B
1978 23ft SeaCraft Seavette 502HP ZZ502 Mercruiser TRS Drive-Sold-UGH!
1998 28ft Carolina Classic 7.4 Volvo Penta Duo Prop
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