Hi, still in the process in getting familiar with the details of my 70 GS Stage 1. Now, I did notice that port on the back side of the Q-Jet. While every hose in the engine compartment seems to be properly connected I am wondering what to do with this. Just plug it or leave it as it is? Thanks Carsten
I've seen various things hook to this manifold vacuum port, some shop manuals say it's for the brake booster, but for my 67 it connects to the gulp valve for the A.I.R. injection system (smog). If you don't need it, plug it.
Plugged mine on the 68. Mine only needs vacuum advance, PCV, dont need it plug it. It's a full vacuum port so if you have anything that needs full manifold vacuum it can be used.
That vacuum port goes to the vacuum storage tank located on the firewall. That tank stores vacuum for the various climate control functions.
Is that vacuum strage tank only present in A/C equipped cars? Mine does not have A/C and I do not have such a tank.
you could get a vacume tank and get a vacume trunk button that will open your trunk . A 68 Riviera like me here has one.