1957 312 4bbl PVC conversion

[ShelbyGTH]

Has anyone converted the down draft tube to a PCV valve ? I am wondering if you notice any difference driving it other than maybe less fumes behind the car....

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[Ward 57]

I've seen nothing but bad issues trying to convert to a PCV valve. If you have noticeable fumes when driving you have other issues.

 

[cokefirst]

The PCV system works fine if properly installed and maintained. You can get a block to sit under the carburetor where you hook your vacuum hose. You remove the road draft tube and install valve with a rubber grommet into the area where the road draft tube connects to the valley pan. Now for the problem. The original valley pan had a box with some sort of fibrous material that was supposed to separate the oil from the fumes in the valley pan area so that the oil did not go out the road draft tube. After 65+ years, that fibrous material has disintegrated and is no longer doing the job. The fix is to remove the intake and valley pan and refill the box with a mesh material to stop the oil from being sucked into the PCV valve and eventually the engine. You can find tech articles on how to do this and make the system function as it should.

 

[ShelbyGTH]

Ok that makes sense, thank you for the info. Enjoy your day!

 

[dustymtn]

Has anyone converted the down draft tube to a PCV valve ? I am wondering if you notice any difference driving it other than maybe less fumes behind the car....

I bought & installed a kit form Larry's (also available from CASCO). I did it to reduce emissions. I've noticed less oil smell standing still.