Bought a 1967 Dart 225 six, automatic, not running, about a year ago. Since then I had the head rebuilt (with hardened valve seats for unleaded gas) I replaced the harmonic balancer, timing chain and gears. The original exhaust manifold was cracked, so I scrounged around in the junk yards, finding one on a 170 six in a 66 dodge pickup. I had the distributor rebuilt (new bushings) and installed a pertronix electronic ignition conversion kit. New coil, ballast resistor, and spark plug wires. Bought a factory rebuilt Holley 1920. Got the Dart running. Adjusted the timing, carburetor, and valves. Sounds like a new engine, smooth and quiet. Checked engine vaccum, pulling a steady 19 in. Sounds good, right? Now the problem. After the car warms to operating temperature and you drive for a couple of miles it wants to die when you come to a stop. Had it checked at a reputable garage. He told me the Carburetor was bad. Since then I have gone through 5 Holley factory rebuilds and 2 from NAPA. All behaved in the same manner. I bought a core in a junkyard and had it rebuilt by a guy locally who has a good reputation. Put it on. Same as others. My choke is working properly and with the engine vaccum still steady at 19 in, I don't think I have a vaccum leak. Exhaust analysis indicates an extremly rich mixture. Plugs foul out quick. (sooty no oil) When I put this back together I took my time and did everything to specs. I need some advice. What have I overlooked? Any suggestions would be appreciated.

BretNAZ@aol.com

Next time it dies, check it for a spark. Running well until it heats up then completely dying often seems to be a symptom of ignition module trouble. The Pertronix I have hasn't done that, but it seems like even with a Holley 1920 your carb won't misbehave that badly.

I had a problem similar to yours with my '68 Valiant. Running down the road and coming to a stop after the motor was warmed up was fine, but when I tried to accelerate the motor would quit. Even though the fuel pump had been replaced sometime before I owned the car, I put a new one on and the problem disappeared. It seems that once the bad pump was warm, it would pump enough gas to run, but would not pump enough at idle to fill the fuel bowl to where the accelerator pump worked properly.

ceh52@quik.com

Bret,

I have experienced the same problem, I think. Does it dye just after driving at highway speed, then it will restart. Does it do it at stop and go speed. Mine only does it after sustained higway speed and will restart right after. Sometimes I can catch it fixing to die and jab the throttle and keep it from dieing. I've been thinking of trying a new fuel pump...even though the one I have is fairly new.
Let me know if you figure it out first.

Trysix


soupitup@msn.com

Could it be vapor locking?
I had a similar problem in one of my buses and that's what it was. Even with two electric fuel pumps, it would vapor lock in any form of warm weather. Finally had to reroute the fuel line and I also added "fins" to the line. Took a little bit of tweaking, but I finally got it!
Good luck,
Dan