Hi - I was wondering if anyone can help me with the PCV hose routing on my 1970 Cutllass pace car - 350 automatic with A/C. can see the hose connector for one end on the quadrajet. But according to the diagrams in the assembly manual there are breathers on each valve cover that are routed into the air cleaner. Where does the PCV valve go ?

thanks, Brad

 

The factory W30 (455) OAI aluminum intake has a fitting in the intake manifold that goes through the intake manifold to the lifter valley for the PVC valve. Don't know how hard it would be to find the proper OAI intake for a 350 that has that needed PVC port in it.
Option 2 would be to simply get a proper grommet for a PVC valve to put in either one of the valve covers which then would go to the Qjet for proper crankcase ventilation.

 

Or, I can modify an iron or AL intake of your choice to have a PCV nipple in the appropriate place:

http://www.ebay.com/itm/150772154268...84.m1555.l2649

Huh, this factory intake has the BOSS, but no nipple in it:

http://www.ebay.com/itm/NOS-1970-OLD...d41d4e&vxp=mtr

 

A 1970 350 with OAI has the PCV value in the LH valve cover and is routed to the base of the caberature. Same setup used on a standrad 350 4 Barrel regardless if it had OAI. It appears the W31 also had the setup…. The 455-W30 SMT has the PVC valve in the intake. The LH valve cover has the filter assembly with hose that runs up to the air - cleaner base…that is how I understand the setups to be…someone correct me if I am wrong here...

 

Brad,

Del70 is correct in that the PCV is routed from the left hand valve cover to the front of the carb. The hole in the left hand side of the air cleaner base has a rubber plug. There is a vent from the air cleaner base to the right hand valve cover.

What you are looking at in the assembly manual is the setup used on the W30. On a 455 W30 intake there is a PCV port in the front of the aluminum manifold that has an elbow attached and the pcv connects to that and the front of the carb. There are filters in each valve cover that are plumbed to each side of the air cleaner base.

If you had a 455 that was not a W30, if you had an auto, it was plumbed like the 350 with the pcv valve in the left valve cover. If you had a 455 and manual tans, it was plumbed like the W30 with the dual ventilation setup.

I think that is all the variations available in '70 for the ram air setup. If not I am sure somone will chime in.

Jim

 

thanks everyone for your help. I understand the routing now. The assembly manual was difficult to follow. I had bought all the "plumbing" for a w30 or manual trans option.

 

This issue is confusing and has its' exceptions. The 71 & 72 Non W30 455 M/T cars with OAI have that W30 style PCV valve system (through the intake manifold with the dual breathers). The CSM says this system is for W-30 only, but the assy manual says it's also for the combo listed above. The intake manifolds (iron with the PCV valve nipple) are hard to find.