just put a edelbrock peformer 600 cfm carb on my sedan. runs ok but when i get on it it starts to stumble and mis. how many turns do you do on the fuel and air mix screws. by the way its a 400 small block chevy.had a holley on it ran good but the carb had some miles on it any help.
Air fuel screws mostly affect idle quality........ But to tune in the screws, hook up a vaccuum gauge to manifold vaccum and adjust screws to highest reading at low idle......
which springs are you using in the carb? Might be using too short a spring making it lean out or too heavy a spring making it too rich depending on the circumstances of it missing and stumbling. Mixture screws are usually 1 1/2 turns or so and set for smooth idle. Turning in lets in more air and out , more fuel. Edelbrock offers step up spring kits that include 5 spring sets to help you get it right. Good luck
vacuum pulls the rods down (lean) and springs push them up (rich). Get the strip kit and go up one size spring (easy operation). You're most likely leaning out because that carb is made for a 350 Chevy V8.
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