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Drive ratio/prop combination❗️❗️❗️❗️ >

Drive ratio/prop combination❗️❗️❗️❗️

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Drive ratio/prop combination❗️❗️❗️❗️

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Old 02-13-2019, 04:40 PM
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Default Drive ratio/prop combination❗️❗️❗️❗️

Hey guys have a 27 fountain fever with a single 500 efi trying to figure out what ratio drive it has a 1:3 or 1:5 running a 24p 4 blade prop, my mechanic is saying it has to be a 1:3 ratio with that small of a prop.
Thanks!
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Old 02-13-2019, 05:58 PM
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What rpm and mph (gps) are you seeing?
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Old 02-13-2019, 06:01 PM
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72 mph 5500 rpm
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Old 02-13-2019, 06:20 PM
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1.5
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Old 02-13-2019, 06:38 PM
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But i am running a small pitch prop.
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Old 02-13-2019, 07:01 PM
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1.5 shows a slip of around 13%- not bad
1.3 shows a slip of around 24%- not good
with a 4 blade I would say it is a 1.5
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Old 02-13-2019, 07:02 PM
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With a 24 prop on my 1.5 I can run 68ish at 5000ish
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Old 02-13-2019, 11:31 PM
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Propeller Calculator / Prop Calculator
My favorite calculator!
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Old 02-14-2019, 01:52 AM
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Is it a Bravo drive??? If so, its a 1.50, 1.36 or 1.25. BMax's are the only drives that had a 1.30.
Most likely its a 1.50
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Old 02-14-2019, 05:06 PM
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Darr again...lol.. Even Griff bit on it...lol..

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