My 1940 ford coupe has a 350 vortec engine that would stall once in a while. I replaced the carburetor with a edelbrock 1406 and replaces a bad coil that works with a mallory unilite distributor. I thought I had fixed the problem. The last time I took it out I had driven about 10 miles and was about a mile from home. Then when pulling up to a red light the engine just died. After cranking on it the engine fired up and I got it home. It's not dirty fuel filter and wasn't low on gas. What am I missing?
If fuel related next time it happens do not try to restart. Pull air cleaner and check for fuel from the discharge nozzle by giving the carb a few pumps.
I had a similar sounding problem earlier this year which I decided was from having the idle ever so slightly too low. The car would conk out after idling for a while (but otherwise drove well). Scary coasting twisty downhill single track mountaineous country lanes to suddenly find the steering had gone unbelievably heavy! Chris
Before you get carried away, make sure that your gas cap is an actual vented cap unless you have a separate vent system on the tank. If you have maybe a quarter of a tank there is enough air in the tank to slowly let the fuel pump build a vacuum in the tank before the vacuum is stronger than the pumps suction. If you got out and opened the gas cap and heard a woosh of air that was air going in the tank. It happened to me on my 51 Merc and it has happened to some others. It took three new "vented" Stant caps to get one that actually vented..
Ha! Right on again, @Mr48chev... My cool O.T. Cal VW started doing the same thing, sometimes 6 miles, sometimes 10. Was busy working on '27 Hiboy at the time, so my wife looked over the bug. Opening the gas cap, she peered down at the vent tube, 3" below the cap. She then proceeded to straighten the steel tube, as the radiator shop had pinched the steel vent tube shut (to vacuum check for leaks after repair!) Thanks, Joey. Best wife I've had yet!
Carry a timing light, string it into the car if possible, put it on the coil wire when cranking over and aim the light in a dark place. Just to make sure you are getting spark to the cap.
Check for spark, unilite module maybe failing, let in run in driveway at high idle, if it stops running, cool distributor body with wet rag chilled in freezer, see if it starts.