600 edelbrock secondary bog.

when you look down the primaries, and work the accelerator linkage with your hand (engine off), but already warmed up, do you see instantaneous, strong squirt of fuel?
Is it a new, virgin Edelbrock or is it used. Sometimes the accelerator pump cup seal is not sealing to the pump "well" well. There is also at least one, maybe two check balls in the accelerator circuit. Look at a rebuild kit exploded view, and assembly notes for location and size of ball(s). There might be a brass check "rod w/tapered end" under the accelerator squirter cover. Sorry, I haven't worked on one for like 25yrs, and I've slept since then, so memory is a little fuzzy.
Make real sure the float level is correct. Hope this helps.