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Rpms for a 502 and prop size

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Rpms for a 502 and prop size

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Old 07-09-2017, 09:04 PM
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Default Rpms for a 502 and prop size

Hi i have a 1989 pachanga 27 with a newer 502 carberated motor in it, not really sure what i should be turning for Rpms in it. I have a 21 pitch bravo 3 blade that 5100 to 5300 which I felt was to many Rpms, and i have on it right now a 24 balastic 3 blade that was turning 4500 to 4600 rpms the other day. I would like to jump up to a 4 blade or 5 blade but not sure what pitch would be most efficient
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Old 07-09-2017, 09:46 PM
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502 mag from mercury revs to 5050. 4600 is wayyy to low and will wear it out by lugging it.

Last edited by indysupra; 07-10-2017 at 04:49 AM. Reason: Typo
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Old 07-10-2017, 01:17 AM
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502 mag is rated 4600-5000rpms at WOT and running slightly above is that is fine.

If your engine has a cam that is larger than stock, then running closer to 5200-5400 rpms is where ti should be.
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Old 07-10-2017, 05:28 AM
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My tac could also be off seeing the boats pushing 30 yr old and the gauges are original. haven't had a problem coming out of the hole with it on the 24 pitch prop, and the water conditions haven't been the greatest with a lot of current.
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