So far it's has one episode of frantic roadside troubleshooting: Halfway between Albuquerque and Socorro the engine lost considerable power with occasional misfires. Top speed reduced from 70 down to 45mph. After limping into town I checked the points, condenser, and installed new plugs + coil. AFR looked fine though. None of the parts helped but I noticed the spark plugs were really white as the ceramic was slightly eroded and one was missing an electrode. Finally after retarding the distributor (in the dark with no timing light) it seemed back to normal. Perhaps descending from my garage at 7200' down below 5000' may have induced some pre-ignition? Or maybe it took a while for that broken electrode to bounce out the exhaust valve?
I think it started with 10 degrees advance while idling. Not bothering to check for several months i finally measured the ignition timing ~8 degrees retarded after top center!? So i put it right at 0 where it is now.
I'm assuming the flywheel BB is at 0 degrees...
Anyhow... it's put on a couple thousand miles since the incident without issue.
