Pontiac 400 Engine - Intakes?

[AM.MSCL]

No matter how cool this looks to people that look at the car :hooray:
I have to believe it is way too much fuel being put into the motor. Plus a lot of the other things on the motor just give the feel of show car.
I believe the carbs are both 600 cfms also a PVC is attached to the front vacuum port on the front carb.



The car does run decent and only needs a 30 second run to idle on its own. NOTE: 4 Speed Manual Tranny! I don't know the CAM specs.
No bogging or cutting out. Acceleration comments below.
Every great once in a while it will diesel (2 knocks and shut off)
In 2nd or 3rd gear and low RPMs: punch the pedal: wait a few seconds to get moving
In 3rd or 4th gear and High RPMs: punch the pedal: the front end starts lifting and responsive ass hauling
Start the car up (sitting a few minutes, an hour or two, day or more) 90% of the time have to crank the motor 30 seconds to a minute; with the pedal to the floor to start it up. Pumping the pedal makes it worse.
Another point of interest is it takes some major RPMs to get it moving from a dead stop at a light. (no tach but hearing the motor rev)

I am really thinking of switching out to a Edlebrock 2156 intake with what cfm carb?
Any other known intakes that are good that will still fit under the stock style hood?
Thanks
Ray