I don't see an issue with the valves failing prematurely, valves in the heater control for instance stay energized as long as you have the vent selected that way, hours on end. And yes, the idea is to hopefully find a three way valve. The schematic for the heater system shows the change over valves to be three way. Going to see if I can find some literature on the over boost valve.

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1982 300sd, new project car to restore

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