Quote: sounds like the cam.. I wouldn't spend another dime on parts. Buddy of mine had the same problem last year with his 440-6 charger. The center carb sounded like a popcorn machine, turned out to be three flat lobes on the cam. Pull the valve covers and roll the engine manually to verify...or pull the intake, they're sooooooo easy on a big block.
So i did some carb tuning research in my spare time and what i found out since the engine clears up fine after about 2500 RPM when it moves to a more richer circut it would apper that like a lot of others said it's a LEAN issue and not an ignition issue as i first thought.
So i guess that the next step is to try swapping another similar carb out and see if that fixes the problem. That is my plan for next week.