Have you done something that might have affected rotor phasing? Any way that the pickup coil wires to the distributor became reversed? Google "rotor phasing"
This end was not touched so don't think so, besides we think the backfire is caused by the MSD Blaster 3 not getting enough voltage at higher revs.. will find out today as just got up and the sun is actually out!!! so about to swap over back to the Blaster 2 thats been on for 1000 miles and fix the minor fuel leak at Holley blue pump, only leaks very slight when idling, guess someone tried servicing it without replacing the gasket.. so hopefully by end of day I'll know if the backfire is gone and if it runs good at timing at 17 (from the previous 32 peak 50!!!) also need to check under valve cover driver side as there is a creaky noise when cold??? (everything up top is 1000 mile new)
On the other subject of running with no ballast and causing issue?? I've read in countless places Inc MSD forum that its fine although it can shorten coil life.. but at $60 its replaceable if indeed the case? eve nthe MSD instructions said fit a ballast only if running points? which I'm not.. I'm just wondering what others think? not saying the poster is wrong, but I don't know the guy and have read on hotrod sites and MSD forums and enclosed instructions... but to confirm at present running the 4 connection ballast, stock ECU.
