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Old 05 October 2007, 17:15   #1
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Prop slip

Having searched a good number number of threads through the forum, I've found calculators to help me work out what mine is, but I dont understand the importance of what it means ? and how it is relevant ?, and how i can improve my set up.. Is slip bad or good, and when does it become a detriment to performance ? My 275 does 5800 rpm witha 1.85 ratio leg that achieves 62 mph tops ?
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Old 05 October 2007, 17:53   #2
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What pitch prop is that?

Obviously the lower the slip the better. 10% is considered pretty good.
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Old 05 October 2007, 17:56   #3
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Obviously the lower the slip the better. 10% is considered pretty good.
Why's that then, I currently have 15% slip, but i bet mine is quicker than yours!
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Old 05 October 2007, 18:00   #4
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basically rpm x pitch = theoretical distance travelled in one revolution

distance actually travelled in one min (6.2 miles converted to inches) / theoretical distance = a percentage

85% or better is good. Slip is sorta good and bad, depending on what's going on at any given moment with the engine. You want a little when starting from a dead stop to avoid lugging the engine. While running consistently, you want as little slip as possible though.
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Old 05 October 2007, 18:09   #5
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basically rpm x pitch = theoretical distance travelled in one revolution

distance actually travelled in one min (6.2 miles converted to inches) / theoretical distance = a percentage
You've been down the pub, haven't you Captn?
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Old 05 October 2007, 18:16   #6
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Why's that then, I currently have 15% slip, but i bet mine is quicker than yours!
Doh I would never have guessed.......
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Old 05 October 2007, 18:17   #7
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Doh I would never have guessed.......

Probably not as fast as your mates though!
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Old 05 October 2007, 18:21   #8
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Probably not as fast as your mates though!
Ahh you know Jonathan Jones as well then........
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Old 05 October 2007, 18:22   #9
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Funny enough, yes, I do, rather well infact!
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Old 05 October 2007, 18:24   #10
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Thought you would somehow.
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