yellow rose
Overnight Sensation
I am first going to check voltage at idle. If normal, then I will try again to see if backfire is confined to only one side or if it is both sides. I don’t want to exaggerate, but I have had the plugs in and out roughly 240,000 times in the last 8 months. They are a little dark, but not oily. No signs of detonation. If I get stuck I may post some pictures. A week ago, what I really needed were ideas. You gave them to me in spades. Now, what I really need is a day off to work on this thing. I will let you know what I find.
You have enough ignition that the plugs should not have any color on the porcelain. If there is color there, it’s rich at idle, and I’d probably say pig rich.