PORTED VACUUM SWITCH

[eddyw]

What is this part doing, where to connect...

All info is welcome(see photo).

Also on the photo, why no tube to the heat shield?

The other photo, is this the right vacuum line routing (black/blue).

Thanks,

Eddy

 

[Boss1Ray]

Looks like vacuum advance and retard and carb vacuum?

Ray

 

[72HCODE]

I wrote this up

http://www.7173mustangs.com/thread-under-the-hood-mysteries-distributor-vaccum-control-valve

It's a good thing.

It's a engine overheat fail safe for the engine in AC cars.

Actually looking at the photo you posted a little better that looks like the spark advance switch.

It changes the spark timing as the engine warms up.

It's like automatic dwell adjustment with electronic ignitions systems.