intake connections

O.k. since there was a post on the hose that goes to the anti-run on valve, I started looking closer under the hood. My intake manifold is in question. The vacuum line to the dist. is connected to the front. There is a plug (bolt) in the middle and nothing is connected to the rear(plugged with a blocked hose). If I move the dist. vacuum line to the rear, the engine idle speed increases (yes, I block the front connecting point). Should the line to the anti-run on vavle be connected to the front or rear of the intake, or middle? Where should the dist. vacuum line connect to?
Also, there is a fat little bulbous plastic thing inbetween the dist. vacuum line and the intake. I assume this is a filter? Help?

I should have included that this is while the engine is cold and the choke was pulled out while doing all testing(moving of vacuum line).

>If I move the dist. vacuum line to the rear, the engine idle >speed increases (yes, I block the front connecting >point).

O.k. now, where should the like correctly be and should I even have that little bulbous plastic thing in the line?
Thanks again!

Duh..
It may be important to note that the front intake point is a hex fitting that is larger than the rear one.

Also, the reason that there is no line to the anti-run on valve is that the anti-run on valve has broken at the point where the line should go on.

O.k. so my under-hood knowledge is not the greatest but I am trying and if there is more I need to clearify, please let me know. Thanks.

(Just joking) Seriously though, I would like to help but your description of your setup leaves me a little confused on what is going on and what your looking to achieve.

The intake "looks" like a tube that is mounted parallel to the motor. It is mounted against the motor on the driver's side. On top of it are places to attache fittings.
As you look at it from the driver's side, is the vacuum line from the distributor advance connected to the right (rear) or left (front) of the intake manifold?

As I remember mine, the vac advance tube comes off the top of the manifold behind the rear carb( I have a 72). It is a small fitting. The other ports are plugged on my car except for a larger port near the front of the manifold which I believe once went to the anti run on valve( which I no longer have). This port has a rubber cap on it. The anti run on valve worked by opening the manifold to the world thus bleeding off the vacumn co that no fuel would be sucked into the engine to allow the engine to continue to run. Mine does fine without it and unless I was reqired by law I would not replace it.

I don't know what year you have, but for early cars the vac line for the distributer is the vacc. advance line. It's supposed to have a large capsule shaped thing in the middle. This is a filter. One end connects to the distributer and the other connects directly to the rear carb. with a short rubber hose. I think later cars used Transmission-controlled spark advance. I don't know much about this, but I know it goes from the distributer to a solenoid valve then to the manifold. Thos might be for auto trans only, but again, I don't know. If this is the case, the vacc. line should only go to the carb, not the manifold, unless you have auto trans. Hope someone else can follow through with more info.
Good luck.

I had asked the question about the run on valve. I have a 78 with zs carb. My vacuum advance is to the rear of the intake manifold, and I will be putting the run on valve hose on the front manifold fitting (it was plugged).