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Discussion Starter · #1 ·
Hi everyone, i'm new to this site and i have some questions about a Quadrajet carb

First of all, this is a Ford FE 390 engine from a 1964 Thunderbird. I bought a carburetor adapter and a Quadrajet carburetor.
I recently read that the vacuum port at the back of the carburetor is for power brakes and the pcv port is on the front of the carb, so on the picture below there is a blue circle, there it is the pcv valve and the hose is attatched to the vacuum port at the back of the carburetor, so my question is; can i do it that way or do i have to route the hose to the front port?

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So here it comes the other question; by watching the other picture there is two small vacuum ports, which of these is for distributor advance?

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Thanks in advance
 

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The large port on the back has a pipe thread connection. If you don’t need it for power brakes, use a threaded plug to seal it. The large port on the lower front is for the PCV, and it should be easy run a 3/8” line from there over to a PCV valve in the valve cover. IIRC, the small port on the right side of your picture has full manifold vacuum, and the left side is ported, but Its different on some carbs so I would verify with a vacuum gauge.
 

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Both the large ports (front and back) are straight manifold vacuum. It doesn't matter which one is used for power brakes and which is used for PCV. GM used the rear one for power brakes only because it was closer to the brake booster and they probably saved a penny or two in shorter lines on each car they made. Functionally they are identical.
 

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Discussion Starter · #5 ·
Right side is ported, left side is manifold vac.
Are you sure that’s a pcv?
I don’t see a carb adaptor. They are usually 1/2 inch thick.
Show us the adaptor.
Yes, i'm pretty sure that's the pcv because i don't see nothing similar anywhere else
The adaptor can be seen on the pictures, maybe a little zoom in? I used the Mr. Gasket 1932
 

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Discussion Starter · #6 ·
Both the large ports (front and back) are straight manifold vacuum. It doesn't matter which one is used for power brakes and which is used for PCV. GM used the rear one for power brakes only because it was closer to the brake booster and they probably saved a penny or two in shorter lines on each car they made. Functionally they are identical.
Well, i hooked the pcv hose to the rear port thinking about the location that if i'm not mistaken both ports are located at the same level of the carb, basically at the base of it, but i had to ask to be sure because i don't want to screw anything as i am on a budget right now
 

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Discussion Starter · #7 ·
I hope to test the fuel pressure for tomorrow, just to know if i'll have to buy a fuel pressure regulator. Someone told me about using a Jeep Grand Wagoneer fuel filter that has a return line to act not just like a ilter but like a fuel pressure regulator. What do you think about it?

Thank you all for your feedback
 
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