I believe an Edelbrock 1406 carburetor is a copy of a Carter AFB. It is a square bore carburetor. Unfortunately the secondary's are not readily adjustable on that type of carb. Ideally, when you stomp on the loud pedal, the secondary's should smoothly open over about 1 1/2 to 2 seconds. You can basically do the same thing with your right foot. Smoothly push the gas pedal down over about 2 seconds and see if that "fixes" the bog.

Also, like Tech said, it's not going to be a strong runner off idle with that big cam in it.