I have a '67 Plymouth Satellite, 400/727. I've had the car for about a year and this winter made some upgrades/modifications. The car had sat and was hardly driven last few years, so I just went ahead and replaced the entire fuel system after seeing how much junk was in the carb. It has a new fuel tank/sending unit, 3/8 ss lines, Mancini carter fuel pump (so its not as high of pressure), braided fuel line ( with filter mid line) up to 650 Eddy AVS2. I also replaced the heavy intake with a Performer RPM. New plugs and wires (Firecore). Orange box and MSD blaster 2 coil on top of intake manifold. New Napa Battery. Ammeter says battery is charging when car is running. Here is the problem and it has happened to me twice now and I am pulling my hair out. Car fired up fine in my garage, two pumps on the gas pedal and she ran fine. It does smell a little rich and I need to adjust that. Drove 3 miles and shut the car off, but it wouldn't fire back up. Plenty of fuel (I could smell it) but car wont start and sounds like it is slow to turn over (like a dying batter). I also replaced the ECU (orange box) and that didn't do it either. I recharged battery and tried jumping to no avail. 2.5 hours later tried the car again and it fired right up. Battery shows consistent 12.4 or so volts. The car does have headers. Before all fuel system work, the car took forever to start, but it also had a Holley fuel pump with a fuel regulator on it. I've been trying to look at other posts for the problem as well Could this be an issue with the starter and heat soak on it? Any help is appreciated and trying to give as much information as a I can. I want to narrow this down so I can enjoy my car, but not throw tons of money at trial and error. Thanks in advance!