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Old 10 August 2016, 09:17   #1
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Searider and Mercury 50 prop choice

My 2012 Mercury 50 2 stroke currently has a 12 pitch prop, which was what it came with from factory.
As it is on a light boat I'm having decent hole shot but cavitation and top end issues. It seems to be over revving by 1000 rpm.

What prop would you suggest?
I've been reading around and seen matth mention a spitfire prop, would that be ideal as a 4 blade would still give good hole shot?

Thanks whizz.
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Old 10 August 2016, 17:28   #2
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14 pitch 3 blade gave me 44mph on my SR4 with a 2 stroke merc 50. If you're 1000 rpm adrift, it'll probably be about right.
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Old 11 August 2016, 09:21   #3
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1000rpm is a lot, I would think 14 or even 15 pitch is required
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Old 12 August 2016, 08:33   #4
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Quote:
Originally Posted by Nos4r2 View Post
14 pitch 3 blade gave me 44mph on my SR4 with a 2 stroke merc 50. If you're 1000 rpm adrift, it'll probably be about right.

Do you know the diameter of the prop?
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Old 12 August 2016, 09:05   #5
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12x14 or 10.5 x 15 4 blade spitfire prob would be good to aim for.
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Old 12 August 2016, 18:30   #6
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Quote:
Originally Posted by Whizzbang View Post
Do you know the diameter of the prop?
10 3/8 diameter was what I was running.
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Old 15 August 2016, 19:34   #7
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12x14 or 10.5 x 15 4 blade spitfire prob would be good to aim for.

What performance were you getting from a 4 blade? I guess they would give a reasonable top speed but as it is a 4 blade is hole shot still reasonable?
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