Carburetor Question - Is this a good call?

crashcaptn said
Hey thanks man - So I should have stated some of those factors first.

Engine is strong and has passed with flying colors its leak down test and compression tests. Valves were just adjusted about a month ago and they're proper. Timing was checked and was already perfect last weekend (I don't have the numbers here but i'll get them soon). Basics are actually done, but good on you for asking. I've had what feels like fuel delivery issues for a while AND what I also left out was that gas mileage is horrible, carbon build-up on the exhaust tips, pulled spark plugs and they're showing signs of too much fuel, and when i'm on the freeway after about 10 mins of driving at 50 MPG i start blowing grayish smoke (no oil consumption, no coolant consumption). I rebuild the Holley myself and that was a mistake so I had a very good shop here in San Diego rebuild it professionally. Still. Issues.

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crashcaptn said
Hey thanks man - So I should have stated some of those factors first.

Engine is strong and has passed with flying colors its leak down test and compression tests. Valves were just adjusted about a month ago and they're proper. Timing was checked and was already perfect last weekend (I don't have the numbers here but i'll get them soon). Basics are actually done, but good on you for asking. I've had what feels like fuel delivery issues for a while AND what I also left out was that gas mileage is horrible, carbon build-up on the exhaust tips, pulled spark plugs and they're showing signs of too much fuel, and when i'm on the freeway after about 10 mins of driving at 50 MPG i start blowing grayish smoke (no oil consumption, no coolant consumption). I rebuild the Holley myself and that was a mistake so I had a very good shop here in San Diego rebuild it professionally. Still. Issues.

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I have a 340+6 AAR ‘Cuda, and my center carb had this issue. Turns out a backfire blew out my power valve. New Holleys have a check valve to prevent this, but older carbs do not.
If the power valve blows out, no amount of jet change, mixture adjustment, or float level adjustment will help. The power valve will go full ritch because it’s no longer a restriction to the flow of fuel at the prescribed vacuum level. Check it out.