Carb vacuum ports
Thread Starter
Race Director
Joined: Oct 2000
Posts: 11,891
Likes: 3
From: Kansas City, MO ...I'd like to go fishing and catch a fishstick. That'd be convenient. - Mitch Hedberg
Carb vacuum ports
I bought a used Qjet that appears to be from a '76 Corvette based on the stampings. I'm replacing a lot of the emissions systems on my '80 and now it's time to route the vacuum lines and I'm not sure I have it right. Please correct me if I'm wrong. (Port #4 is under the fuel inlet block)
1. Distributor TVS
2. Fuel Vapor Cannister
3. Air Pump Diverter valve
4. PCV/Fuel Vapor Cannister
5. EGR TVS
6. ?
7. Brake Booster
8. Temp Switch on the air cleaner assembly
I have the following info to help me route this, but I think I have more ports than are needed.
Also, I purchased a used air cleaner assembly from an '81. There is a tube off the drivers side that I don't know what it connects to. (It's numbered 8 but should be 9)
1. Distributor TVS
2. Fuel Vapor Cannister
3. Air Pump Diverter valve
4. PCV/Fuel Vapor Cannister
5. EGR TVS
6. ?
7. Brake Booster
8. Temp Switch on the air cleaner assembly
I have the following info to help me route this, but I think I have more ports than are needed.
Also, I purchased a used air cleaner assembly from an '81. There is a tube off the drivers side that I don't know what it connects to. (It's numbered 8 but should be 9)
Melting Slicks
Joined: Aug 2004
Posts: 2,906
Likes: 228
From: Oakbank Manitoba
#9 isn't installed on my factory (1980) dual snorkel air cleaner.
#6 can be capped off as it isn't used/located on a 1980 Quardrajet.
Missing on the top front of the quadrajet is the bowl vent line that goes to the cannister. You can see the undrilled boss for it just right of #3 and just above the blue TVS. It was used to vent the fuel vapor fron the fuel bowl back to the cannister on later year carbs.
#6 can be capped off as it isn't used/located on a 1980 Quardrajet.
Missing on the top front of the quadrajet is the bowl vent line that goes to the cannister. You can see the undrilled boss for it just right of #3 and just above the blue TVS. It was used to vent the fuel vapor fron the fuel bowl back to the cannister on later year carbs.
