Mark-

I've had the MSD box in for about 4 months, no problems. The problem started while I was on the freeway, noticing a slight miss. The next day, I'd go down the street and it'd pop and miss real bad. I then switched coils and carbs and it still ran bad. For some reason, I replaced my regular carb and it ran fine going around the block. The next day, it started missing and popping again. I wouldn't think the box went bad, I checked all ground wires and they look okay. so I'm wondering about the ballast resistor and whether thats bad.

Ron