'67 Newport 383ci Starved For Fuel or Vacuum issue?

[Whiteh2omac]

My stock everything '67 started acting like the carb was fouled, chuga-lug, chuga-lug, not getting the fuel it needs so I decided rather than just clean and rebuild the 2bbl Stromberg, I might as well do the upgrade I've been planning. So I swapped the intake for a 4bbl. 2806301 cast intake and installed an Edelbrock Performance 1406 carb (based on guidance from this forum), new fuel line and filter from pump, new gas tank, flushed the fuel lines, etc. Everything went together well and looked good. Fired up and ran great for approx 12.65 seconds and right back to the chuga-lug, chuga-lug, not getting the fuel it needs symptoms again. Same as before. The fuel delivery system is totally clean and the carb is protected with an inline filter so it stands to reason that fuel is likely not the issue. So what is? Maybe a vacuum issue? Any ideas from MOPAR aficionados?

 

[Welder guy]

When my 383 was acting like this it I pulled the plug wires off and on the cap one by one till I found the one that made no difference in how it ran , it was cylinder #7 . It turned out to be the distributor cap . It’s an easy check that doesn’t cost anything. In the end I decided to change the cap/rotor, plugs and wires and the car has ran great ever since.

 

[HWYCRZR]

Check your fuel pressure. When you shut it off after chugging, take your air cleaner off and stroke the carb linkage. Are you getting a good solid stream out of the accelerator pump? If not check your fuel pump pressure and the length of your fuel pump rod. They can wear over the years causing lower fuel pressure/flow.
If you have good flow through the accelerator pump move on to the electrical.

 

[Big_John]

chuga-lug, chuga-lug,

Sorry.... Could not resist.

 

[Big_John]

Joking aside...

I would check the fuel pump as said. Disconnect the fuel line at the filter and remove the coil wire (just cause) . Run a rubber hose to a soda bottle and crank the engine over. It should put a lot of fuel into the bottle in a short time.

Could be a pump, could be the pump push rod is worn out... or both.

 

[CBODY67]

Is the gas cap correct for the car? Are the tank vents open? Might remove the gas cap and run the engine and see if it makes any difference.

Just curious,
CBODY67