No-load Misfire Puzzle

I guess technically, I can't defend "seat of the pants timing". There have been a couple of times, when running aftermarket components, I've timed per spec, and still had to reset my timing, while doing a driving shakedown to get my best performance. I wasn't dealing with this kind of a problem however. There are some good ideas listed in these postings, and I will do a follow up. It's over 90 degrees here again today, so will wait til weather cools down a bit to mess with it. I'm going to try to combat the heat, with a glass of beer and tomato juice.