390 double pumper vacuum

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Yup. Someone has done some witch doctor work on that carburetor. It's a 390 alright, obviously by the tiny venturi. Not only has someone drilled air bypass holes in all four throttle plates, but they also removed all four pressed in high speed air bleeds from the top. It's not junk, but it certainly needs work to operate on anything. Four new throttle plates and new high speed air bleeds at least. I would go ahead and remove the four idle air bleeds and tap all eight holes to accept replaceable air bleeds. That would give you a variety of adjustment there. But then, I would also either modify the existing metering blocks to accept idle fuel restrictors and power valve restrictors, OR get new metering blocks that already have all of that. Either way, that carburetor needs a bit of work and or money thrown at it.
 
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Switched out this carb for a different one , still dealing with high idle (2500+) got it started and running but once it’s in gear it dies

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skinnysteve72 said:
Switched out this carb for a different one , still dealing with high idle (2500+) got it started and running but once it’s in gear it dies

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1) That 390 would've started out with screw-in Hi & Low/Idle air bleeds, and power valves. But since it was a NAPCAR legal unit for restrictor-plate comp., the air bleeds & the PV passages could've been employed to sneak air around the venturis, " Witch Doctor" work as posted above. It's a geat carb for somebody other than You..lol..
2) If an entirely different carb has resulted in a 2,500rpm idle, You either have an air leak, the throttles are on a fast-idle step, or the throttles also have idle-compensating holes drilled in them. The VS Holley 600 had those depending on the list#, so You'll need to verify the presence or absence of these items/conditions.
 
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