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Old 08 March 2007, 15:22   #1
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3 blade to 4 blade

Has anyone changed from a 3 bladed prop to a 4 blader,why, and did they notice any decernable difference? I'm trying to achieve better bow lift, when trimmed out, I find someone moving forward will bring the hull down into contact with the water,lowering the speed. I've done a little research and maybe going from three to four might give better control..i'm just guessing at the moment. Does anyone have experience of this problem,has anyone solved it by other means? I'm keen to learn here.
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Old 08 March 2007, 16:04   #2
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I was under the impression that a 4-blade promoted better stern lift. Helps to get on-plane quicker due to the larger surface area pushing water.

All things being equal (pitch, diameter, general blade shape) expect to lose a couple hundred rpm adding the extra blade. And a few mph off the top end at the same rpm. You should get more efficient cruise fuel economy, though.

jky
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Old 08 March 2007, 23:27   #3
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ditto results

Did it last year.

Better acceleration
Lost a few knots at wot.
better economy at mid range.
Much better prop grip in rough weather with subsequent better responsivness
more economical when carryingheavy loads

enjoy
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Old 09 March 2007, 06:27   #4
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Cheers,

Pretty much what I thought.


zero'd i on the Powertech 4 blader 15 1/4x24 OFS series (current one is 14 1/2 x25) the american bass boat forums tend to steer towards this manufacturer as the best.

Importing form the states, half the dosh...if it doesn't work though..








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Did it last year.

Better acceleration
Lost a few knots at wot.
better economy at mid range.
Much better prop grip in rough weather with subsequent better responsivness
more economical when carryingheavy loads

enjoy
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Old 09 March 2007, 06:34   #5
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if it doesn't work though..
Then you sell it on Ebay and make a profit

Win-win situation.
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Old 09 March 2007, 07:08   #6
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up early this morn nos,

Not being an e bayer I'd probably balls it up

Am I seeing "Prince of Darkness imports" on the horizon ?.



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Then you sell it on Ebay and make a profit

Win-win situation.
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Old 10 March 2007, 08:30   #7
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Then you sell it on Ebay and make a profit
Win-win situation.
Personally, I'd toss the prop and some cash at a prop shop and get it tuned the way you want.

jky
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Old 10 March 2007, 08:47   #8
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up early this morn nos,

Not being an e bayer I'd probably balls it up

Am I seeing "Prince of Darkness imports" on the horizon ?.
You would if I could get away with it but the import duty payable on lots of large items from the USA makes it non-viable and the fines are horrendous.
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Old 10 March 2007, 22:48   #9
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You would if I could get away with it but the import duty payable on lots of large items from the USA makes it non-viable and the fines are horrendous.
Not if you bring it home in your check in luggage like I've just done with an entire Sea Star Steering system
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Old 10 March 2007, 22:56   #10
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Not if you bring it home in your check in luggage like I've just done with an entire Sea Star Steering system
That only works if you can blag free flights
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Old 10 March 2007, 23:02   #11
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I'll give you a shout next time I go. Yamaha F150 for $11500 anyone?
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