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Gordon wasn't completely joking when he said the CB Performance Magnaspark is the 'best Pertronix you can get'.
The problem is Pertronix makes the electronic module (that replaces points) but uses the same questionable quality distributor body that most of the inexpensive no-name distributors use. It's the distributor body (and its weights-and-springs advance mechanism) that determines the consistency of the spark and the shape of the advance curve. The Pertronix is notoriously weak in that department.
A number of us with Pertronix dizzies have had lingering firing and miss problems that were at first attributed to carbs, but that instantly went away when we switched to distributors that are mechanically better. The Magnaspark is a reasonably-priced alternative that seems to be much better built mechanically than the Pertronix distributors currently available.
I don't know for certain if the Magnaspark will fit on a 912 motor, but I'm sure CB Performance could tell you, or probably half the folks here.
Stay tuned.
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