Just because an HEI has electronics that last three days past forever doesn't mean it is maintenance-free. There are still shaft bushings in the housing to wear, and that centrifugal advance system under the rotor doesn't get lubed unless you take the rotor off periodically and put a little lithium-base grease like Lubriplate on the moving parts. One of the big problems is that the early ones didn't have bushings on the advance weights, just steel-on-steel, and the pivot pins would wear out. Newer ones have brass or plastic bushings and bigger pins. You'll get better performance and/or gas mileage with the centrifugal advance working right. Was it stuck in the "advance" or the "retard" position?

About once a year, pull the rotor and lube the advance system. There should be NO contact between the cap and the rotor except for the rotor center touching the carbon pivot button. A cap and rotor should last at least 50K miles between changes. Have fun!
Jerry

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