1970 distributor what is this box?

[OCTAVIOUS]

So I have what I believe to be a highly sought after 70 distributor 3438222 date coded late 69 it came with my car and should be the original for my engine.

It has a brown box near the vac advance with an electrical connection..

What is that box for?

 

[toolmanmike]

So I have what I believe to be a highly sought after 70 distributor 3438222 date coded late 69 it came with my car and should be the original for my engine.

It has a brown box near the vac advance with an electrical connection..

What is that box for?

View attachment 1900318

View attachment 1900319

@HALIFAXHOPS can fill you in

 

[Jerry Hall]

You should have a solenoid on the passengers side of the carburetor that the box controls. It's operation is in the service manual. I adjusted mine to not work as I couldn't get the proper result per the manual. It's still electrically operational but the solenoid touches nothing. Look it up as from memory I don't remember.

 

[DeltaV]

Post in thread 'Vacuum advance w/ solenoid' Vacuum advance w/ solenoid


"Retard solenoid" in the FSM.

 

[Vaanth]

So I have what I believe to be a highly sought after 70 distributor 3438222 date coded late 69 it came with my car and should be the original for my engine.

It has a brown box near the vac advance with an electrical connection..

What is that box for?

View attachment 1900318

View attachment 1900319

The item on the distributor pictured is the solenoid and vacuum chamber assembly. The assembly was introduced on the 1970 big block wedge engines.

The solenoid retards the ignition timing when the carburetor throttle is closed at curb idle. The retard allows more initial timing advance to not hamper starting of the engine and subsequent improved low speed response.

The following three images from the 1970 Service Highlights detail the unit, its function, checking and connections:

As noted, it is also covered in the 1970 factory service manual.

 

[OCTAVIOUS]

Well that’s a new one on me!

Thanks For the info

 

[Lefty71]

I had one on a '71 Cbody. Its does retard. Im curious what H-Hops has to say.....but i threw that sucker away in '79 and threw an Accel dual point in....that 440 ran great afterwards.

 

[toolmanmike]

70 440 4 barrel single point.

 

[HALIFAXHOPS]

3 year only HP emission's thing. Basically a emissions item Big POS and rarely works right and is very expensive since it is NOS and a crap shoot if it is good or not. Post 5 basically explains it. Talked to the engineer that designed it also he fought it all the way.

 

[Jerry Hall]

3 year only HP emission's thing. Basically a emissions item Big POS and rarely works right and is very expensive since it is NOS and a crap shoot if it is good or not. Post 5 basically explains it. Talked to the engineer that designed it also he fought it all the way.

No wonder I couldn't get mine to work per the service manual. My distributor was also NOS in 2000 when I bought it for my Superbird restoration. Basically it's on the car but does nothing now. Thanks for the information.