I have a 69 with 350, Edelbrock Perormer intake and Rochester Quadrajet carb and HEI distributor. When I remove the vacuum line going to distributor and plug it,set timing (12 deg) .When I reconnect vacuum line timing remains the same.The vacuum line is connected to the port that is front pass side of carb. Other is another vacuum port on right side of carb and when I put vac gauge on it it slowly builds vac at idle. There is a third port in middle of carb higher up that has vacuum at idle.I connected distributor to this port and at idle vac advanced to approx 30 set. What port should i be connected to.
Thanks