Will Delco-Remy centrifugal advance springs work in a MP distributor?

Bill Crowell said

Two silver (light) springs and the full 28 degrees of centrifugal seems to be the hot ticket! Static timing of 13 degrees BTDC with the vacuum advance connected, and it would probably like more. No detonation and the MoPower is good, but the secondary air door on my Thermoquad isn't opening as early as I would like it to, and I am wondering if that is because I need more advance or because I need to adjust the carb.

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Something I’ve found that I’ve never caught with a timing light is that when the springs get too light, the advance mechanism will do weird things. Like advance a bit...maybe 2 or 3 degrees and then retard 4 or 5 and then start to advance again.

I do not understand why this is, or even how it happens. Certainly advance weight shape and mass have something to do with it, but it’s certainly above my education level to sort it out and possibly correct it.

Interestingly enough, when I replace the light springs with something else I get an all most identical curve without the advance/retard/advance situation.

The next time it happens I’ll take a video of it. Someday, when I have time to actually screw around with it, and if I have spare weights for that particular advance mechanism I’ll make changes to the weights to see what happens.

Or, maybe I’ll find a book that explains it.