51PlymouthFastback

This would not had helped me. I have the Langdon's Stovebolt HEI distributor. I mentioned it in the first post.

PROBLEM SOLVED. After doing some of the things mentioned here, I took my buddy for a test drive, and it was still doing the coughing and hesitating. At that point he declared, "It's a misfire!" So, we parked it, got back under the hood and took another look. First thing we did was look under the distributor cap, where we found a build up of dust or crud on one of the contact points that is the underside of the terminals on top of the cap. I cleaned the under side of the cap with brake cleaner and cleaned all the contact points plus the rotor tip with 1500 grit sand paper. Gave it some nice clean contacts. We took it for another test drive and it ran great! Thanks everyone for all the great tips.

Fernando; I just replaced the fuel pump because it was leaking (crack where the fitting is seated) and put in a brand new one. It's still doing it. Veemoney. I looked at the fuel filter, and while there is stuff floating around in there, it doesn't look like it's anywhere near enough to cause my problem. That being said, at this point I will replace it any way just to be thorough. I'll check the vacuum line as well, although I have to mention that all rubber hoses in there are pretty new. Vacuum, Fuel line, etc.

My car has developed a really frustrating problem, I'm hoping one of you can help me with. First, a little about my engine. I've got a Plymouth Flathead 6 bored .60 over, and running an Edgy head and dual carb intake. I have two Speedway 9 Super 7 carbs, and the Langdon's HEI distributor. Recently my car developed this hacking coughing kind of stutter as I accelerate through 1st and 2nd gear. If I can get the car up to a good cruising speed in 3rd gear, the problem seems to go away. It feels like the gas is getting intermittently blocked then released. When it's 'coughing' I lose all power. When the car is just sitting there idling, I can rev the engine and it does not do it. Only when under load, and moving forward. Any ideas?

I drive my 51 Plymouth Concord at least once a week. Sometimes more, depending on what's going on.