...even it is IS your car, Todd....!
Me likee.... Went to a hot rod cruise in several months ago and there was a gold '49 Merc lead sled there...all slammed on the pavement, chopped top, no door handles, etc,...lake pipes, etc. Waaay cool. Loved it. Everyone took noticed when he pulled in to the Sonic but didn't park....just looped around the building. When he got to the other side, he goosed the throttle and flames about 6 feet long erupted from his tail pipes in the rear. TOOOOOO COOOL! The crowd went nuts...! Standing ovation! He looped around the drive in again and parked it. In a moment or two he was flooded with lookers...
Anyway...back to KK's problems. Karl...I would replace the coil - or at least, swap it with a known good coil as Ron61 suggests. Also...the misfiring is most probably the source of the fuel in the side pipes, and then when it fires...the exhaust torches off the gas fumes ... Awwww, yeah....we're talkin' way cool here, Karl...you'd be a hit at cruise-ins, no doubt..
But, I'd also check everything ignition related....distributor drive gear, too. It's possible you may have sheared off the roll pin that holds the drive gear on the distributor shaft. Not uncommon, and a pretty cheap fix, too. Your problem sounds like your losing fire in one or more of the cylinders, and of course all the valves continue to work to pump the gasoline rich air into the cylinders where it's not burned and then exits through the exhaust valve into your headers and sidepipes. Then, when the plug fires again...BOOM!, one fireball coming up! (Cool...me likee!)
But...I'd investigate everything in your ignition system, from plugs and wires, to distributor cap, condensor(s), dwell angle, coil, etc. etc. Then, if all that checks out and you STILL have the problem, check the distributor drive gear and look for a sheared roll pin.
In fact...I believe I'd check the distrbutor drive gear first....! Don't want that sucker to separate from the distributor and fall down into the crankcase. You may get lucky and have it not get caught in something....and then again.... Well, you get my drift, I'm sure...
Let us know what you find out. I'm thinkin' this is all about your ignition system.