I posted this in a different thread but now I can not find it.
My trans modulater hard line is plugged into a ported vacuum port
The hei vacuum advance is plugged into a full vacuum port.
car has weak acceleration , but starts and idles great , should I flip flop the lines ?
it is a 650 edlebrock carb.
I know I need a tune up (other than spark plugs)but I want to get it as correct as possible before bringing the car in to a shop.

Joe Pavado , you mentioned in the other thread that the trans mod line should NOT be on a ported vacuum port . Is this correct ?
THANKS IN ADVANCE

 

A TH 400 needs manifold vacuum.

 

It is a th400 , So I guess I need to hook the trans line to the intake somewhere ?

 

Yep. Or a manifold vacuum source on your carburetor.

 

ALL automatic transmissions with a vacuum modulator need full manifold vacuum to the modulator, not ported vacuum.

 

So if I use the full vacuum port on the carb for the trans line , will it be ok if the hei vacuum advance is plugged into the ported spot on the carb ?

 

You need to experiment to see if the car runs better with ported or full manifold vacuum to the distributor. It's perfectly acceptable to put a tee in the line and connect both to manifold vacuum if the car runs better that way.

 

Sorry I dont know much about vacuum , but is the full vacuum port on the carb the same as full manifold vacuum?
I am loooking at my owners manual for the carb and it states that one port is ported and one is full vacuum on the front of the carb.
This is great when we can actually chat instead of waiting hours for help , I sure appriciate it .

 

Yes, it's just an additional port provided as a convenience. It is exactly the same as a tee screwed directly into a manifold runner. Ported vacuum, on the other hand, is specific to the carb and is connected to a port (get it?) in the venturi that is above the throttle blade at idle but then is uncovered shortly after the throttle is moved off idle. Once the port is uncovered, ported vacuum is virtually the same as manifold vacuum.

 

There should also be a manifold vacuum fitting on the manifold in front of the carb, that is where my trans vacuum is tapped into.

 

GOT it Joe , I will experiment with it. Thanks alot !!