Willy, If this Edelbrock is an AFB design look carefully at the carb top near the float valve area to see if there is a brass hex plug, 3/4 hex if I remember correctly.On some of the AFB and etc there is a fine screen under the plug which can blind and cause fuel starvation.probably one for primary and another for secondary.
Study Jerrys suggestions and interest in the line before the pump carefully.Small leaks here can be tough to suspect but really cause trouble.I have proven leaks here by directing the fuel flow after the pump onto a container and look for air entrained in the flow whth the engine running on what was in the carb.Many times they won't leak with the engine shut down.
