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Shouldn't he hook vacuum advance to front carb vacuum fitting? That's where Mines hooked up. Manifold vacuum is constant right? Where carb vacuum increases with rpm increase. I might be wrong about this tho. If I am continue and ignore me. Lol
Come on Rusty I'm disappointed that you didn't put a music video in this post. You're slacking man!Be more specific??
Open loop or closed?
This quoted info seems key.
Lookin at you, float level.
So ..the quad leaks?
Internally?
It's 8 pages now Rick..you doin alright buddy?
Your timing isn't set at 0°??
Rick can fix it but I reckon he's gonna need moar coffee I guess.
Prolly gonna have to open it up, the Quad.
I can easily see that you need to change the intake manifold gaskets - they don't last 35 years.
As for the brakes? My money rides on a leaking wheel cylinder. Think real hard about removing the rear wheels for a brake inspection - A.S.A.P.
Safety first kids !
Yes manifold vacuum is constant. For decades. Manufacturers used manifold vacuum for vacuum advance. Using manifold vacuum was the way to do it before emissions became a problem. If you use ported vacuum at idle you won't have any vacuum advance at idle,manifold vacuum and ported vacuum match after you are out of idle,so you don't get more vacuum from a ported source than a manifold source,just manifold you get more at idle. Cars will normally idle better and the throttle plates can be closed further at idle using a manifold vacuum source. Ported lights the charge late at idle so the charge finishes burning in the exhaust,so it cleans up exhaust emissions. Which is also why I tell people to retard their timing if they are having problems passing emission tests. P.S your carbureator also uses manifold vacuum to sense load,the further you are in the throttle,the less vacuum you have,so vacuum advance goes away due to low vacuum and your carbureator starts adding fuel,this is how vacuum leaks can make you run rich and kill your gas milage.
Learned me something today. Thanks for the clarification.
I worded that wrong,I hope you saw my mistake. I already edited it. You get the same amount of vacuum with ported or manifold once you are out of idle. But manifold gives you more timing at idle.
The early quadrajets that used the thermostatic spring for the choke operation have the manifold vacuum in the spot he has it hooked up at. That is the correct location. When they went to the hot air choke in ~78, you end up with the big choke piece on the side that covers up that port and is used to draw the air through the choke system to heat up the spring. That is when they added the manifold port on the front of the carb and routed it through a TVS on the thermostat housing.
www.gmsquarebody.com
He moved it to brakes and they're helping him over there.
