Choke pull off
 

On my 70 gto manual trans with restored original carb. The question is on the choke pull off there is two ports one of them has a Vacuum line going to the carburetor on the other port what connects to that. Thanks Tom

The "other" port connects to a vacuum tank mounted on passenger inner fender and is a part of the "Delayed Vacuum Break System".
This system delayes choke valve opening a few seconds to allow the manifold to be wetted and prevent stalling due to leanness.