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Old 11 August 2005, 11:47   #1
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Country: UK - England
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New Props for 150 Optimax

I am looking for new props for my 150hp Optimax.

Currently running a 19" Laser II, looking for:

a) Something to get more speed

b) Something for more grip in tight turns and pulling up skiers etc

Aware that this will be two different props.

Advice and sellers wellcome.

Many thanks,

James
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Old 11 August 2005, 11:48   #2
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What rev's are you pulling at WOT with the 19" prop?
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Old 11 August 2005, 11:58   #3
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What speed are you getting at the moment?
Give Julie a call at steel developments, very help full!
http://www.steeldevelopments.co.uk/
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Old 11 August 2005, 12:03   #4
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Getting about 5500 revs fully trimmed and can make 46 knots with 4 in the boat, looking to go above the elusive 50 barrier!!
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Old 11 August 2005, 12:07   #5
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Quote:
Originally Posted by jimc
Getting about 5500 revs fully trimmed and can make 46 knots with 4 in the boat, looking to go above the elusive 50 barrier!!
Clean & wax the hull , kick 3 people out!
Job done & saved 600 on new props
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Old 12 August 2005, 04:32   #6
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My Opti 150 max'es out at 5750, so you are not far off. The solent hull has a reputation for being quick but i'm not sure 50knts is attainable with a 150. Are you trimming right out to get these rev's?

I don't know a huge amount about different props but my simplastic view would say try a 17" laser II, try and borrow one if possiable. I don't have one i'm afraid.

I can make 46knts with a 21" laser II @ 5200 RPM and the same speed @ 5500 RPM with a 19", never tried a 17" so please report back if you try it.
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Old 12 August 2005, 06:51   #7
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Props

If your pulling 5500 rpm and the opti maxes at 5750 then more speed cant be obtained. To gain the extra 250 rpm you'd need to fit either a smaller prop or one of a lesser pitch. This will give better pull out but less speed. Another trick is to lightly sand the hull with some fine wet and dry paper. 800 grit with soapy water is good. The top dinghy racers do this, it causes the hull it ride on a layer of minute bubbles which "releases" the hull and reduce drag. Waxing the hull tends to do the opposite and create suction between the hull and the water. It sounds as if 46 knts might be yer lot though.
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Old 12 August 2005, 07:06   #8
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Quote:
Originally Posted by Mollulnan
If your pulling 5500 rpm and the opti maxes at 5750 then more speed cant be obtained. To gain the extra 250 rpm you'd need to fit either a smaller prop or one of a lesser pitch. This will give better pull out but less speed. Another trick is to lightly sand the hull with some fine wet and dry paper. 800 grit with soapy water is good. The top dinghy racers do this, it causes the hull it ride on a layer of minute bubbles which "releases" the hull and reduce drag. Waxing the hull tends to do the opposite and create suction between the hull and the water. It sounds as if 46 knts might be yer lot though.
So a sandy bottom goes faster hey
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Old 12 August 2005, 09:54   #9
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Sandy bottom

....may give you a rash also!
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Originally Posted by Nick Hearne
So a sandy bottom goes faster hey
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Old 12 August 2005, 09:56   #10
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My osprey is anti-fouled, often wondered how much this knocks the top speed.
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