I am about ready to pull my hair out on this one. I have a 383 in my car that is fresh. he night we got it started, it ran great, held it at 2,000 to break the cam in and it purred like a kitten. It sat outside usually during the week and was driven into the shop on weekends to work on it. One night we set the timing and dwell (yes, I am running points) and things seemed OK. One day about a week later I notice a popping noise when holding the throttle at a steady RPM, usually around 2,000 or higher. I checked the distributor, cap and rotor, nothing seemed out of order, but I replaced the cap and rotor for good measure. Same issue. I have replaced the ballast resistor because it wasn't working as a resistor anymore so I also replaced the points and condenser. Same issue. Replaced ignition wires, coil, and even spark plugs. After the spark plugs, it runs much better, but still has an annoying popping but not so bad as before. I checked for vacuum leaks and found nothing.

All I am looking for at this point is maybe another area to look into that I haven't tried already.

Any help is appreciated.

Tanks, Paul

Not saying it did, but if a exhaust lobe of the cam went away it will pop through the carb when held at a steady RPM...

This is a popping through the exhaust. I have re-built the carb just to make sure it was free of debris and gunk. This is a puzzle that has got me very, very confused.

Confirm your firing order, cylinders 5 and 7 esp, as it's easy to cross them, and have the engine seem fine at idle, but have a slight and steady exhaust pop, or engine vibration under load, or high RPM

just double and triple checked wiring and firing order. Everything is in order. I forgot to specify that this isn't a steady popping, but a random popping. I thougt I might have had water in the fuel, but tried a known good container with fresh fuel and still have this issue.

Thanks for all the help so far guys.

Check voltage at coil , should be 9 or 10 volts while runing .Had a bad battery , low charge , and car would not RPM and misfired at 2k .

I had an intake leak thru the valley pan and it was popping like that. Fixed the vacuum leak and the popping was gone.

Clean your spark plugs too. I've had a 383 and a 440 do this just moving them around the shop and not running them long.
Edit: Sorry I didn't catch that you'd already changed plugs in your original post.