Tom M'Guinn

Congrats finding the problem. You wonder why the set screw keeps backing out? Use plenty of loctite on it. Not sure you get retarded timing if it slips. Doesn't the DME fire when it fires? If the rotor was misaligned, maybe you were just arcing inside the cap -- maybe even to the wrong post if it's real far off. May be worth taking another look to see if the cap is still good?

Danno

Yeah, your timing wasn't retarded. Just probably lost 90% of your spark energy going nowhere. Some of the spark did make it across and it was enough to ignite a low-density partial-throttle mixture. But when you opened up the throttle more and gave it boost, that little spark wasn't enough.