The picture I posted is a generic Eddy carb (since you didn't mention WHICH Edelbrock carb and manifold you have) and the vacuum port locations could vary slightly. Look up your model carb (stamped on the left lower corner by the mounting stud) and look it up to confirm your port locations.
Then try the ported vacuum for your dist. advance. Barring any vacuum leaks on the intake (as others have mentioned), I'll bet your bog disappears.
By the way, when you set your timing, you did it with the vacuum advance disconnected and the port plugged, right?