FE-FC Holden Discussion Forum

Can anyone please help on what goes where when it comes to vacuum.
I would appreciate any help by those who also know about triple strombergs.

I need to hook up the following:

- Triple CD150's on a factory HOLDEN Manifold
- Electronic Dizzy
- Remote Brake Booster
- Trimatic

I don;t need wipers ( have electronic ones ).

I've heard some things need manifold vacuum, and others need a vacuum before the butterflies, but I can;t see any outlets on the carbs, hence I need a triple stromberg guru !

Any help on what plumbs into what would be helpful.

Cheers

mark

Hi Mark.

The vacuum advance line from the dissy goes to the small fitting on the carby, there should be one there if there the correct type, the front one would be easier.

The brake vacuum booster & the Tri-Matic modulator can go together on any available threaded manifold fitting.

I noticed you didn't mention PCV, if you're running EH/HD/HR 'walking stick' pipe or a 'breather can' disregard what I'm about to say, if not, read on.

The most common plumbing mistake guys make when they plumb up the vacuum lines is to incorrectly fit PCV.
Have a look at any factory installation & you will notice 2 things.

1. They never connect a PCV line at the same fitting as any other hose.
2. The PCV is always connected so as to equally distribute the 'air leak' to all cylinders.

Most set-ups have the PCV just beneath the carby (on 6s) or on the carby base itself on most V8s & some later 6s.

The only time Holden had a PCV combined with multiple carbies was on the XU-1s. If you have a look at an original example, you will notice how they use a T-piece & then hoses to go in between the 1-2 then 2-3 carbies. If you're going to use a PCV system (recommended) then follow their plan.

Dr Terry.

Thanks Dr Terry.   Yes I do have the factory LC XU1 set up, but was thinking of NOT running the PCV valve,as I didn;t really see what value it has other than sucking back in any un burnt gases.

I had thought of using the vacuum outlets ( between 1 & 2 and 2 & 3 carbs ) to run the booster and trimatic.

I've also been told to run a vacuum can to store excess vacuum due to the lumpier XU1 cam I'm running.

Please tell me why the PCV valve is so important.
Also, I can't for the life of me find any pipe coming off the CD 150 stromberg carb for the dizzy vacuum.

ANy ideas on what i'm looking for ?

THanks again !

mark

There is a small pipe on the top of each carby and towards the manifold. Block of two and use the other one. Can send you a photo of a set if you want.
Cheers Graham

Graham, a photo would be great...as I'm either blind or stupid.

Given that I find this pipe next time I look, is it best to block off the other 2 as you say, or is it best to plumb all 3 into one line to give even more vacuum ?

Thanks

Mark

I'm pretty sure the Pcv is to relieve crank case pressure to stop blowing out seals

Ok! Photo on its way.
Graham