I've had this happen a few times this month.
Car's running fine, no issues, suddenly stumbles to a halt and flat out DIES.
Starter fluid down the bores, no go.
Pull the coil wire, ground to the chassis, hot spark.
Last night I was driving home, car was running great...turned a corner, got a slight misfire, kept running fine...got down the road about 1/4 mile, and it puked its guts...started running like garbage, misfiring all over the place. I pulled into a parking lot to troubleshoot it, and it idled fine, no issues, but as soon as gave it even a little throttle, it would miss like mad, getting one or two good hits, freewheeling, another hit or two, backfire out the pipe, etc. It finally died and wouldn't restart. As I said, I verified that it's getting the critical three - gas, air, spark - and nothing happens. When it died, I was getting sufficient fuel pressure at the gauge I put in the line just before the carbs, so I'm positive the pump is all right.
At this point I'm betting the ignition module is out of sync. That's the only explanation I can come up with. It's been running without issues for a long time until this month. The distributor is on tight, the cap and rotor look good.
Details on my setup:
L28, N42 block & head, '70 round tops, electric pump at the tank, filter before the pump and at the block, fuel visible in the filter at the block, Chrysler ECU setup.