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Old 22 September 2005, 14:36   #41
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Originally Posted by jwalker
Des, are you sure you have that the correct way around. Normally the prop runs slower than the engine. Just did a little calc for you... If your engine is at 2800, your prop pitch is 21, slip about 20% and ratio is 1.26 then you should be making 30.4kts.
JW does 1.32:1 then come out as 28 knots, which is what I normally achieve at 2800 revs ?

Pete
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Old 22 September 2005, 14:40   #42
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Originally Posted by Pete7
JW does 1.32:1 then come out as 28 knots, which is what I normally achieve at 2800 revs ?

Pete
29.33kts
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Old 22 September 2005, 14:52   #43
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Well that does make sense I wasn’t sure which way the ratio worked, I had assumed more prop revs = more speed. My boat has always been fast compared to others and this would explain it. Having said that it looses it when full Des
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