Plugs and Wires
I went ahead and replaced the plugs and wires for good measure. Nothing special, just some store-brand wires and some basic Autolite plugs, gapped to 0.035".
Cap and Rotor
When I pulled off the distributor cap, there was a pleasant surprise. Somebody already removed the old points and installed a Pertronix Ignitor module instead. I forgot to take a picture, but it's one of these:
Vast improvement over points, IMO. Longer lasting, hotter firing, nothing to adjust or mess with, generally more reliable.
So, the original ballast resistor was working, but it's cracked and the connections pretty badly corroded. I installed a new one.
I replaced the ancient rusty coil with a nice new "Flame Thrower" coil.
The distributor looked old but working. I'm going to keep it for now. However, the ignition timing was obviously way off, and the distributor was turned around so that the wire was smashed against the block, and the vacuum pod was hitting the engine. I pulled it out and "reclocked" it so the position kind of matches this pic:
So, the various internet people and the service manual don't all seem to agree about where the timing should be set, and how one should set it. Advice ranges from 2°ATDC at idle, to 15°BTDC at idle to 35°BTDC at 3000 RPM, to all kinds of voodoo.
I used the time-tested technique of adjusting total advance:
- I fired up the engine and turned the distributor just to get it to stay running, then let it idle and warm up.
- I got the engine up to 2500rpm, then advanced the timing until it started to ping a little bit, then backed it off a couple degrees.
- This got me a high-rpm "total" advance of about 17°, and at idle with the vacuum disconnected, base timing of about 4°. I'm sure this is far from "perfect", but it's good enough for me, for now.
I'll follow that procedure again and readjust this more carefully after I get the carburetor all jetted and dialed in.