Frank, the switch-over valves are also RPM controlled? Hunh, you learn something new every day. I always thought they were activated by the 70C temperature sensor and the A/C solenoid. Talk about redundancy.

I believe '75 and later models went to the VR ignition system which eliminated the ignition points removing the need for ignition retard.

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“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
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