dizzy vac line to front of carb

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Jarhead79

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Was messing with the distributor today because it was loose, had to fix the plate that holds the dizzy, while doing so a friend pointed out that my vacuum advance was plumbed to a post in the back of the intake, I moved the hose to the front of the carb, seemed to make a huge difference, can anyone give me some advice or info on the how to hook up the egr right?
 

Quadrajet Power

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EGR vacuum port is typically on passenger side front of base plate at an angle. It supplies manifold vacuum.
Distributor could be hooked to manifold or ported vacuum depending on your tune and when you want advance applied.

Just to expand, manifold vacuum has vacuum at idle at the vacuum outlet. Ported vacuum only sullied vacuum when the throttle blades are open.
 

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Depending on the setup generally manifold vacuum is better. But you may to make adjustments.
 

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Yeah, manifold vac for the dizzy with around 16 deg advance at idle with it disconnected. Ported vac for the egr but there may be other components in between to control when it's applied.
 

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Well now I'm second guessing my victory, lol. I guess I need to figure out how this thing truly needs to be with vac lines and egr etc. s there any step by steps I can go by to do this the right way?
 

Georgeb

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First, did you get your carb "rich running" issue figured out?
Regarding the carb, is the choke opening up properly when the truck is warmed up. I think regardless of where you attach the advance if your running rich it will need to be addressed. Set your timing around 12 degrees and start looking at your carb.
 

Jarhead79

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Haven't figured out if it's rich or not, I can smell fuel but with these old trucks in not familiar with whether or not it is rich, I talked to a member on here about an issue a friend noticed about a little gas shooting up from inside the carb a little when adjusting my dizzy, right now I'm redoing my vacuum lines and trying to see if I can get everything plumbed right, my brake booster was plumbed to front of carb, my pub was plumbed to the rear of the carb, my egr was completely disconnected, there is a metal plate with holes just in front of the egr, one has a metal tube going to the choke, the other hole is missing the tube and I'm assuming that it is supposed to go to the egr possibly? Can I bypass that with a vac line and go from egr straight to the choke?
 

Georgeb

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Haven't figured out if it's rich or not, I can smell fuel but with these old trucks in not familiar with whether or not it is rich, I talked to a member on here about an issue a friend noticed about a little gas shooting up from inside the carb a little when adjusting my dizzy, right now I'm redoing my vacuum lines and trying to see if I can get everything plumbed right, my brake booster was plumbed to front of carb, my pub was plumbed to the rear of the carb, my egr was completely disconnected, there is a metal plate with holes just in front of the egr, one has a metal tube going to the choke, the other hole is missing the tube and I'm assuming that it is supposed to go to the egr possibly? Can I bypass that with a vac line and go from egr straight to the choke?

So PCV to the front.
Brake booster to the back.
Vac adavance to manifold vac
The tube for the choke only has one line to the choke and has nothng to do with the EGR.
EGR to ported vac unless you don't need to smog test the truck then leave it disconnected for now and plug all the rest of the vac ports.
Set your ignition timing to 12 degrees and see what you get.
If there is gas spurting up out of the carb that's an issue you will need to address.
 

Jarhead79

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Was watching videos last night and figured something else out, I don't have the choke pull off on the rear of the carb, I rerouted all my vac lines where the should be, left egr disconnected, to use it I think I need a new part, it's a little plate with two metal tubes coming out of it, one tube is connected to the Choke the other is missing the tube, I'm assuming this is where the egr is routed to maybe?
 

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Jarhead79

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Somethings missing! Lol
 

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firebane

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That is just for a rear choke pulloff which isn't necessary.
 

Quadrajet Power

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That is just for a rear choke pulloff which isn't necessary.

Correct. No rear necessary or needed. Even though the casting has the place for it, I don't show that your carb number had one originally. Either way, you don't need it.
 

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