Jet size help

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Jan 20, 2002 | 08:20 PM

73Ranger

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Jet size help

I picked up a 500 cfm Holley 2bbl carb the other day to replace the motorcraft 2bbl on my stock 360. The Holley was last run on a race car and has 76 main jets. Can somebody tell me what size main jets will put me in the ballpark for a 73 F-100 360 C-6 with 3.00:1 rear end? I know I'll have to fine tune after the carb is installed on my truck, I'm just looking for a generic starting size.

Thanks,
Matt N.

Jan 20, 2002 | 09:46 PM

pntrbil

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Jet size help

I know those 2 bl Holley's inside and out, both the 500 and 350 CFM flavor, and I wouldn't even hazard a guess! LOL! I've got a jet box that runs from 64's to 99's that I think only cost $30. Then I'd try 70's and 80's to see which WAY works the best. I suppose I'd guess the 70's but that's only a guess. Another thing to remember is to always change at least 2 sizes when you get close. They aren't perfect so a skinny 74 could be real close to a fat 73. If ya change by two's at least you know you changed something.

Besides the main jets you can use either a 30 or 50cc pump shot chamber. Pump cams come in a plethora of shapes and sizes and yes, 4bbl ones will work! The sqirters vary by size and type. Tube, straight, anti-pullover that I've seen. And then there's a whole range of power valves. Definitely a tunable carb.

I've got a 500 on my Pinto motor turning 8 grand twice a lap and I'm tunin' up a 350 CFM on a 302 in a 68 Mustang as I type.

Rattle my cage anytime and I'll ya help all I can.