My SBC is running like crap. I used a timing light on each plug wire to see if one may be not working. One was not working so I fixed that one. Another was making the timing light flash faster than the rest. I got that one blinking right. I then started it and it ran pretty good. I turned it off to move the timing light out of the cab so I could time it via the marks on the crank. I turned it back on and it ran crappy again. I retested the wires and now I have 2 that make the timing light go crazy. I guess I'll have to maybe give it the spray tonight when it's dark out to see if it's arcing. Maybe get a new set of plug wires? Could something have gone wrong on the HEI unit?