Air Bubbles In Fuel Line

Did you say you have a Quadrajet on a Square bore intake???

That is going to be a major miss match. Big huge secondary butterflies trying to swing open in the smaller square bore openings.

Did you use a spread bore to square bore adapter?

Thinking that quadrajet is too much for your 318.

If you can get an Edelbrock 1406 600 cfm square bore carb, put that on there for a test > should straighten right out. They work very well for the 318s cammed or not.

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