I would try replacing the power valve since it did back fire (even though the street avengers are supposed to have million mile power valves). Are you running the correct number power valve based upon the amount of vacuum you are pulling?
Do you have a stuck float? Pull the bowls and check. Needle and seat stuck?
Did you balance the carb using the mixture screws?
Is it just running fat at idle, or does it stumble when you try to rev it up? Check the stroke on the squirter to make sure you dont have a lean or rich bog.
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'96 Z/28 Convert Sorta Pro Touring
1967 Chevelle SS396 Convertible On the way to entry level PT
2013 Ford SVT Raptor Supercab Pro fuel consumer
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