Name these parts

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Joined
Jul 6, 2015
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Location
Iowa
My Car
1973 Mustang Grande 351C 2v
First part let's call it part A

Mounted to the front drivers side valve cover right behind AC compressor. Has two vac line attachments a ground and a power lead?

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And now Part B. Mounted just behind part A. Has Three wires. One comes from the same loom that the lead going to Part A came from, one goes to AC compressor clutch, and one circles back over and ties to the small (resistor looking thing below the selinoid).

image.jpeg

 
Part 'A' I would name "Allen"

Part 'B' I would name "Betty"

Allen looks like a stock emissions control device. Where do the vacuum lines lead? It looks like the one has a check valve in line.

Betty does not look stock to me.

 
Vac lines route as follows. Both sides of Part A vac lines have check valves going the opposite direction and loop back to each other with a T. That line also is attached with a T to vac advance. That line then leads back to a plug in the water pump with two other vac lines one going to the manifold and one to the carb. Here is a pic of the plug in the water pump with vac lines attached. As for part B I think it is a relay someone installed for the AC clutch.

image.jpg

 
Sorry no help Jason

But makes me happy that all those extra pieces that have nothing to do with

"Go Fast" got tossed decades ago! (No Concourse Here)

Now I do recognize some of the wire connectors I have that are not connected to anything.

Cheers

Paul

 
Update on Part B. I traced the wires and it is just a relay someone installed for the AC clutch. My wiring has been hacked on this car multiple times. The PO even went as far as installing relays for the head lights and high beams. While I appreciate someone took the time to do this and did the wiring correctly they were very sloppy and made little or no effort to make it neat and tidy or hide it.

 
73pony, the official Ford nomenclature for part A is, Distributor modulator valve. These started showing up on 72 "NOX" equipped cars, and by 73 (with "Big Brother" watching) was on everything. The purpose of the distributor modulator system was to help reduce carbon monoxide and hydrocarbons. The system was designed to use carburetor venturi vacuum to reduce engine emissions. This was done by controlling distributor spark advance. Ford engineers felt that a retarded spark provided a hotter combustion chamber and exhaust manifold temperatures that caused more complete burning of the fuel. Another early form of emissions controls as the Government tightened their control over the auto manufactures. Surprised that your's is still as complete as it is. A lot of those ended in the junk piles as people "De-smoged" and cleaned up under their hoods! Something my friends enjoyed doing along with tossing rev limiters and Quadrajet carburetors! Since you've already figured out that B is a non Ford part, we will continue to call it Betty as will e suggested. :whistling:

 
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73pony, the official Ford nomenclature for part A is, Distributor modulator valve. These started showing up on on 72 "NOX" equipped cars, and by 73 (with "Big Brother" watching) was on everything. The purpose of the distributor modulator system was to help reduce carbon monoxide and hydrocarbons. The system was designed to use carburetor venturi vacuum to reduce engine emissions. This was done by controlling distributor spark advance. Ford engineers felt that a retarded spark provided a hotter combustion chamber and exhaust manifold temperatures that caused more complete burning of the fuel. Another early form of emissions controls as the Government tightened their control over the auto manufactures. Surprised that your's is still as complete as it is. A lot of those ended in the junk piles as people "De-smoged" and cleaned up under their hoods! Something my friends enjoyed doing along with tossing rev limiters and Quadrajet carburetors! Since you've already figured out that B is a non Ford part, we will continue to call it Betty as will e suggested. :whistling:
Thanks for the info. I still have my original charcoal canister in place as well. I assume then this is why it is connected to the distributor advance with the check valves.

 
So on part A the distributor modulator valve. If I wanted to eliminate that completely would I run the vac advance on the distributor back to the port on the carb or the one going directly into the top of the manifold? I also assume I would bypass the temp switch in the water pump as well and just run direct from one of the ports mentioned about to the dist vac advance.

 
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Ok. Part removed. Tagged and bagged up with all connections marked for future reinstall. I am going to run the advance of manifold vac for a while and see how that goes. I plugged the ported vac line just in case I want to try that later for comparison.

 

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