I see someone else is having problems with a new petronix dist in a thread below. I feel your pain. Been nothing but a headache since installing a new one about a month ago in my 69. Low miles 400 on mild rv rebuild. Thing is, I'm running the same distributor in my 68 and it doesn't miss a beat. Go figure. Having issues with pre detonation and an intermittent miss. Didn't have these issues prior to new dist. Tried pulling the stock module and running it through my MSD 6AL box. Replaced the coil, plugs, wires, cap & rotor, pcv valve. Messed with the adv curve by trying different size springs. Replaced several questionable vacuum hoses, searched for vacuum leaks. Even rebuilt the carb. Probably a few other things too, just slipping my mind right now. Test drove after ever change without any difference...Replacing the coil and module in the dist is pretty much all there is or am I missing something? Next move is to pull that sucker and replace with MSD again. Any and all comments or suggestions are really appreciated at this point. Maybe make adjustments with ball peen hammer?