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Old 22-09-2010, 08:44 PM   #1
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Country: england
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prop help

Need prop help and advice. Scorpion rib with 200 opti, not a speed monster obviously!

Run a 21" laser2 and get 47knots at 5100rpm, ok at high speed, but looses grip very easy and crap at accelerating, in corners and if its VERY rough and trying to plane at low speed, just spins up. want the extra 400-500rpm for speed.

21" high5. Rev limiter and 37.8 knots
19" trophy chickened out at 5800rppm, 44 knots, smooth prop, seemed to like alot of trim which made boat very flighty, however sometimes the forces created made the steering excessively heavy, then at othertimes it was as light as a feather.

Ideally I want extra speed fromt he extra RPM, a constant feel or drive and better grip so I can plane the boat in big swell, any suggestions, very confused why a 21" high five over revved, I thought adding a blade dropped rpm??

Thanks

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Old 22-09-2010, 08:57 PM   #2
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Sounds like a cavatation problem to me, is your engine very deep?
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Old 23-09-2010, 06:44 PM   #3
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Country: england
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Quote:
Originally Posted by Renegade View Post
Sounds like a cavatation problem to me, is your engine very deep?
4inches below....
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Old 25-09-2010, 06:11 PM   #4
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i myself have found if running a high5 they can over rev..up the pitch from your norm if running a 5 plus they seem to like being deeper too on my marshan, holeshot and high speed
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Old 28-09-2010, 06:40 AM   #5
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Have you tried out a 23" lazer 2 worked wonders on my last boat.
I put 23" laser 2 on my new boat and that does 75mph now but then i have got twin 200s.
Am also looking for new props, something to give me more speed, Ill be back in the country by november time, by then will have some new props, maybe you could wait till then to try out 1 of mine.
And yes I agree extra blade would normaly drop the revs but should also increase the speed by a few knots.
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