vacuum tree (PVC) question

[simon]

Chaz, unfortunately I know very little of the ´40/ 46:

hope that helps.

 

[Anonymous]

THANK YOU

evidentally, I have been running for a few months without a distributor spark fitting...and no vacuum on it

aslo, I need a new choke tube...I didnt have a fitting before and it was SUCKING air. now I stuck my old tube on...that stops half way down. atleast its LESS vacuum

man, I KNEW I had something holding me back on gas milage. I am MISSING THE SPARK VALVE THOUGH....HOW DO I GET A REPLACEMENT?

this is an OK carb right?

 

[simon]

Chaz, as far as I understand the holley/autolite 1940/46 is a factory/ shop replacement carb. There were versions that didn´t employ a spark control valve, they had provisions for one in the casting body but no threads cut and no internal connections and air bleeds drilled.
Unless you have a vacuum only advanced load-o-matic distributor, you won´t really need a spark control valve.

Since you´re looking for fuel mileage you can try to hook the front port of the vacuum canister to permanent manifold vacuum and plug the outlets on the carb. Your dizzy needs to be equipped with mechanical (centrifugal) advance!
Leave the rear/top port of the canister alone/ unhooked, and get rid of your vacuum tree. Take her for a test drive and judge by yourself.

 

[Anonymous]

confused a little.....sorry for the many questions as I try to get this straight in my head...so what your saying is that my carb does NOTtake advantage of the dual advance vacuum I have....

1) get rid of the tree...i can do that
2) top of vacuum advance to manifold vacuum...
3) back (horizontal) nipple on vacuum advance... DO WHAT?

simon on your original drawing...the vacuum advance that is on the left..that goes to carb...plug it?

I have all my wires off at work...so I need to route them before I go home..LOL


getting closer to a 2 barrel upgrade...ugh

 

[simon]

First, there isn´t anything on a dual advance vacuum canister that could be regarded as an advantage.

it has two fittings/ nipples/ ports: one on the front, and one sticking out on top.
the front nipple is important, this is your advance connection. the top nipple is the retard connection, it works against the advance at idle.
Back in the day, this was the beginning of the carmakers pace of smog gizmos, resulting in the more and more complex systems of air pumps, vacuum amplifiers, exhaust gas recirculation and other 70´s creepy treehugger fetish stuff.

Back to topic, leave the tree where its at, just disconnect the vacuum lines.
On your vac.canister, unplug the top nipple and just employ the front nipple by connecting it to permanent manifold vacuum - you´ll have to find a vacuum port on your manifold, usually on the log, under the carb flange.

You´ll find your engine idling somewhat higher and smoother.

p.s. tell me if something doesn´t work out, and don´t cut anything, and leave the vacuum tree in place, or you´ll have a major coolant leak!

Obviously, you have fair amounts of free time at work I´ve looked up some links for ya. here´s some interesting reading:

http://www.fordsix.com/forum/viewtopic.php?t=15042

http://www.fordsix.com/forum/viewtopic.php?t=17178

http://www.fordsix.com/forum/viewtopic.php?t=16429

http://www.fordsix.com/forum/viewtopic.php?t=12136

 

[Titleist16]

Simon,

Well, actually my carb says Motorcraft but I think Motorcraft/Autolite are the same that's why I said Autolite. To answer your question, My vacuum canister is on the side of the dizzy and there is a rod that goes from it to inside of the dizzy under the plate. Thanks.

 

[Anonymous]

LOL...me...time at work?

I just manage my time very well. I do the work effienecntly...and then goof off


in all seriuosnes...THANK YOU Simon for walking me thru this