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HP 500 carb jetting w/525 cam

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Old 01-21-2013 | 04:13 PM
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Default HP 500 carb jetting w/525 cam

What i have written down is:
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I've since swapped cams for 525 EFI spec cams(only mod) and was wondering where i should be for jets. Or if nothing else should i stick with the staggered jetting?I know several people on here have said theyve done this swap and figured itd save me the hassle of trial and error.

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Riley
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Old 01-22-2013 | 06:22 AM
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Nobody???
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Old 01-22-2013 | 10:03 PM
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without the increase airflow heads you might be going backwards a little with bigger cam. I would keep same jetting. Do short 30 sec run at WOT and shut down as quick as possible and read plug. Look down in the plug (not the tip) and see if there is tan color. All white means more fuel dark means less fuel.
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Old 01-22-2013 | 10:31 PM
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I put the 525 cams in mine and had them rebuilt and blue printed.I did go up a size but would have to check what the jets are as my memory is a little foggy. Ran great on the dyno but noticed it was a little fat after cruising and coming down to an idle.
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Old 01-22-2013 | 10:44 PM
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Stock jetting should be close. Best bet is to read the plugs, or invest in 02 sensors and a wideband.
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Old 01-24-2013 | 07:35 PM
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Originally Posted by MILD THUNDER
Stock jetting should be close. Best bet is to read the plugs, or invest in 02 sensors and a wideband.
I'm modifying my risers and building my dry tails and was thinking about putting bungs in the bottom for sensors.Only going to run these motors like this for one year but better safe than sorry.I have a carb phobia for whatever reason.
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Old 01-24-2013 | 09:14 PM
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Originally Posted by Rbesola
I'm modifying my risers and building my dry tails and was thinking about putting bungs in the bottom for sensors.Only going to run these motors like this for one year but better safe than sorry.I have a carb phobia for whatever reason.
I hear ya. The 02 deal is a great tuning aid, and will still come in handy when youre ready to build some monsters for that boat.
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