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This manifold sits under the fender on an '85 carbureted GT rag top. A forever project replacing many vacuum lines destroyed during a flash fire under the hood.
Vacuum line goes through the fender wall, I have not yet identified the terminal end. What is it and what does it do?
manifold.jpg
 

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That looks like a part from Ford's carbureted "dark years" emissions system.
It might be a valve for the Thermactor system. Possibly a diverter valve.
You may have some luck searching the Four-eyed forums for information on the Thermactor system on the 84/85 cars.
 

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That looks like a part from Ford's carbureted "dark years" emissions system.
It might be a valve for the Thermactor system. Possibly a diverter valve.
You may have some luck searching the Four-eyed forums for information on the Thermactor system on the 84/85 cars.
Thanks, planning on keeping the smog stuff intact unless it becomes unworkable.
 

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The function of the Thermactor system is to inject air into the exhaust system to keep the catalytic converters at a acceptable temperature. They will quickly overheat and fail without the cooling air.
A common trick, back in the day, was to hollow out the catalytic converters, and to disable the Thermactor system. That way, the exhaust system would look relatively stock during any impromptu inspection. The on board diagnosis system wasn't sophisticated enough, at that time, to recognize the change, and no codes would be triggered, like in more modern vehicles.
 
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