Using vacuum gauge to tune engine?

LovetheA's said
Than you everyone for all the advice and mopardude318 for the video. I do have another question for everyone. Everyone talks about ported and manifold vacuum. If my 383 has an electronic distributor with no vacuum advance how do you set the advanced timing? Also if my manifold doesn’t have a manifold port how can I take vacuum off of the manifold? I adjusted the timing and fuel/air mixture by using the rear port off of the demon carburetor on the passengers side. I read that is what you use. See photo.

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You did it right; "manifold vacuum" is present at that rearward nipple and is what you want the vacuum gauge hooked to for tuning. The front or "ported" nipple flows only as the throttle opens whereas the rear nipple flows all the time. It's all in how their internal passages are routed. As far as a port in the intake manifold itself, the Edelbrock has a big plugged hole in the rear driver side intake runners. That is used as a vacuum source for power brakes, if yours are manual that better be plugged! It's not used for any carb or distributor functions.
If your distributor doesn't have a vacuum advance unit, well, no vacuum advance for you obviously--all you get is the mechanical curve. It can be adjusted in a couple of ways but it depends on your distributor....open it up, see what style it is and start researching. There's plenty of good info here and out on the web. If you get stuck of course post up lots of pics here and ask questions..