When I bought my new Holley I was told to only use one of the two vacume lines. I am confused because I have a vacume line to the Transmission and to the distributer. Do I need both of these and how do I use only one of the vacumme outlets on the carb if I need both things hooked up? Do I need to get a t-conector or something like that. and plug the other one up. THanks for your help.

Nolan

 

Transmission should have direct intake manifold vacuum.
The vacuum advance on distributor housing should have the vacuum from the carburator. With the engine running, the vacuum advance on distributor housing should not have any vacuum with engine idling and should have vacuum with engine at 2000 rpm's.

 

Also one of the vacuum lines on the carb may be manifold vacuum if it gets full vacuum at idle.

 

I perfer using the direct vacuum from intake manifold for transmission modulator.

 

The transmission cvacuum line should attach to the vacuum tree on the bck of the intake manifold.

The distributor vacuum advance hose attachs to the PORTED outlet on the carburetor.

 

You can get your vac. from the carburater or the manifold, the thing to remember is that your vac. advance for your distibuter should go on the high port on the holley, on a 1850 and 3310 it is high front on the passenger side.
And of coures always cap off all unused ports.