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Discussion Starter #1
Does anyone have a diagram of the vacuum lines and where they go on? I have looked online but have not found any pictures or diagrams for the GTO. Any help would be appreciated. I just mounted the original Quadrajet Carb and am having some difficulties.
 

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Above link is incorrect on a RAIV. There is no vacuum switch on the front pass water crossover on a '69 RAIV, instead just a pipe plug in its place. Been several years since worked on '69 RAIV Judge, here's what can remember.

-intake manifold has the common steel small fitting, this is on top of the intake in front of the Qjet. this fitting receives the vac hose going to the T'ed vaccum harness going to the RA upper pan asm, same as RAIII.
-rear of Qjet on center of the base (throttle body) accepts the vac fitting if the car has power brakes. This is either a straight through screw in steel or the straight potmetal fitting with one small port angling backwards ('68-71 style fitting). The large port in the back of the potmetal fitting accepts hose that goes to ck valve on the brake booster. the potmetal fitting with the small port, I believe was only used, when hideaway headlights were ordered.
-if car has manual drums, and std headlights, the port in the rear throttle body of the RA Qjet is blocked.
-that leaves the normal (single diaphragm vac advance) distributor, been too long since had a 7029273 in my hands, need to ck my 7040570, is there a ported vac source on the front of Qjet, drivers side? That's where believe vac signal for the #1941 distributor should come from. I can ck more on this, if needed.
-last, but common deal....if the car is automatic, there will be a port on pass side face of the float bowl of the Qjet. Small piece of rubber hose, then steel vac modulator line running back and down pass side of the T400.
 

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Discussion Starter #4
Thanks,
That was a big help. But I have a few more questions.

I connected the brake booster to the back of the carb (but it does not have a potmetal fitting with a small port for the headlights. I will have to get this as I will need to hook up the headlights at some point.
I hooked my distributor up to the drivers' side at the front of the Q-jet.
I hooked the PCV valve to the larger port on the passenger side of the Q-jet. Is this where I should have hooked my modulator line running to the T400?
I hooked the T400 to the fitting at the front of intake manifold in front of the carb. (I don't think that this was right according to your description). I think I should have hooked the vacuum hose going to the upper portion of the ram air to that (is that correct?)

Where does the PCV hose go?

There are also 2 ports on the bottom of the breather. What goes into there?

Thanks
 

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Pretty sure the PVC hose goes to the manifold in front of the carb.

I hooked the PCV valve to the larger port on the passenger side of the Q-jet. Is this where I should have hooked my modulator line running to the T400?

Yes, I believe so.
I have a '67 GTO and that is where those lines go on my car and it sounds like the rest is correct.
 

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Discussion Starter #7
At this point, the port that it shows in the picture which takes the pcv is blocked off on my manifold.
Still am unsure about the 2 ports in the bottom side of the breather

Thanks
Tom
 

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At this point, the port that it shows in the picture which takes the pcv is blocked off on my manifold.
Still am unsure about the 2 ports in the bottom side of the breather

Thanks
Tom
Sounds like you are missing the thermal sensor that clips into the Ram Air tub. these were a light green and faded to a pale green. Same sensor was used on many '68+ Pontiac air cleaners. later service replacements were molded in black plastic and are incorrect.

Looking at the two images you put up. the "restored" Qjet is no a factory built RA Qjet, prob built off a Buick core. The port that is plugged with a rubber cap, would be in he same spot on a Pontiac Qjet, that is the port for the vac modulator line.
 

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Discussion Starter #9
Sounds like you are missing the thermal sensor that clips into the Ram Air tub. these were a light green and faded to a pale green. Same sensor was used on many '68+ Pontiac air cleaners. later service replacements were molded in black plastic and are incorrect.

Looking at the two images you put up. the "restored" Qjet is no a factory built RA Qjet, prob built off a Buick core. The port that is plugged with a rubber cap, would be in he same spot on a Pontiac Qjet, that is the port for the vac modulator line.
Does the thermal sensor that clips into the bottom RA tub have two ports? If so, where do the vacuum lines run from those ports? Is this a stop along the way to somewhere else? an intermediate thermal sensor for the upper ram air system? I need more info on this area. Any help would be appreciated

If I understood correctly:
a) The vacuum for the headlights runs off the back of the Q-jet
b) The vacuum for the brakes runs from the back of the Q-jet'
c) The vacuum for the PCV runs to the intake manifold at the port closest to the Q-Jet
d) The upper ram air vacuum hose runs (directly?) to the port in front of the PCV port on the intake manifold.
e) The vacuum for the automatic tranny runs to the passenger side front of the Q-jet.
f) The distributor vacuum hose goes to the front dirvers' side port of the Q-jet.

Does this seem correct?

Thanks,
Tom
 

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(a & b) yes...the small angled fitting on the potmetal fitting is for the small vacuum hose that feeds into the hideaway vac harness. i

(c)yes, the big brass 90 degree port that is screwed into the top of the intake her the front of the Qjet.

(d) the hose coming off the small hex headed fitting in the intake, will go up to the thermal sensor in the front bowl area of the RA tub (aircleaner base) two small ports will stick downs through from the small green thermal sensor. There has to be a hole somewhere nearby in the RA tub... I don't remember one, but it's been a while since I worked on a '69 or '70 with RA.. All the showcar pics and the pic of the above RAIV engine from earlier HPP article (now archived by HotRod) show the vac hose coming up out of the inside of the front on the RA tub, then there it heads upward to the back of the upper pan. that T that insects with the vac hoses above the upper pan..then on to the vacuum pods (vac motors)

(e) yes

(f) believe i erred on the location of the ported carb port. The last two Pontiac Qjets I disassembled, vatted, and rebuilt were late '70's Pontiac W72 carbs...total different Qjet with timed spark port, multiple choke pull offs. The pic you have noted above, of the complete '69 RA IV engine, shows a port at a diagonal coming off the pass side front throttle body, then going back to the distributor...too many cobwebs here, but rings a bell... sure looks correct. I can ck some early Pontiac Q jets I have, but have no '69 RA model Qjets. Even though the throttle body used on the '69 RA carbs has a different cast number in a circle than one from a lesser performance '69 Pontiac Qjet, believe I would remember if each numbered throttle body had a ported vac source port in a different spot.
 
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