440 series 26 mallory duel points dis...points issue

A vented point contact is a donut on one side.
A uni-directional spark, moves contact molecules, causing erosion on one, buildup on the other. Ventilated contacts reduce the problem.
Picture of ventilated stator contact.
https://www.google.com/imgres?imgur...ObPAhWCSSYKHdJoDP8QMwhnKDMwMw&iact=mrc&uact=8
Holley add from 61.
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