Source for vacuum for distributor - non original carburettor

[Ian928]

My federal Stag has had all the emissions stuff removed. I have aquired a UK-spec distributor from Stagweber with electronic trigger. My Stag also once in its lifetime has had a carb change to a Autolite 2100 from a Ford Mustang. This carb has a vacuum connection, I have read up about it and it seems this connection is ported vacuum. I found a nice thread on this forum about ported vs manifold vacuum, and I understand that i need manifold vacuum for my distributor.

There are two sources of manifold vauum on my car:

1. The original one on the back of the manifold. As far as I know only the brake booster is connected to this?
2. On the custom adapter plate between the Autolite and the manifold there are a line welded in. I have used this for crankcase ventilation through a Stagweber catch can.

What would you do?

[Ian928]

Here are a couple of pictures of my engine with carburettor.

I also need vacuum for the heater system, could this be T-eed off the same line as the distributor?

F0714E57-121F-4F74-A960-36C386B6CBCC.jpegimage_42752.jpg

[Dieter H. Marschall]

Ask Chris Spain (Stagweber) he is very helpful... Good luck, Dieter.

[KOY 23]

If no luck try https://triumphstag.freeforums.net there's a lot of experience on that site.

[stagwingnut]

I run a Holley carb , the distributer vacuum is a ported one , can’t answer your other questions. Regards Graham

[Ian928]

I run a Holley carb , the distributer vacuum is a ported one , can’t answer your other questions. Regards Graham

Do you also have a Federal Stag? I am under the impression that the UK Stags all had manifold vacuum advance. I have changed the federal distributor to a UK spec one.

[trunt]

I would recheck that you actually need manifold vacuum, it’s normally ported as otherwise it would be over advanced at idle.

The brake booster line is teed off for the a/c vacuum. It’s manifold vacuum.

Terry

[MikeParker]

As Terry says, UK Stags distributors use ported vacuum from the Stromberg carbs. I.e. no vacuum with a closed throttle. If your carbs produce ported vacuum that sounds like a good fit.

Mike

[jbuckl]

If you don’t require the fast warm up system, you could use that manifold tapping. The fitting has a one way valve inside, might need removing.
most I’ve seen are long gone, the spring having turned to dust.
here in the U.K., the fast warm system isn’t operational for long, if at all.

[Ian928]

What system is this? Is it a tapping on the manifold? Sorry for my ignorance!

[trunt]

What system is this? Is it a tapping on the manifold? Sorry for my ignorance!

I think he means the flap actuator? .. If so its on the pedistal for the Strombergs, you dont have it any more..

Ian, Are you sure that you need manifold vacuum? it has nothing to do with the type of carb, its the distributor curve that makes that work. The standard Dizzy is curved for ported vacuum, has the distributor been recurved for Manifold vacuum?