Plumbing PCV into intake - how beneficial is it? (1 Viewer)

[Bullydog]

Finishing up the plumbing right now on a 1HD-FT swap. I currently have the PCV hose venting into the atmosphere.

How much benefit would there be to getting a catch can and plumbing the PCV back into the intake tract? Does the slight vacuum generated by the intake have a worthwhile effect on sealing the rings and whatnot, or is it mostly an environmental and emissions thing?

Engine seems relatively healthy. With the PCV pinched off, I can do the "oil cap" blowby test, and the cap rests smoothly on the valve cover. With the oil cap on, there's a small stream of blowby out of the tube- enough to gently bend a piece of paper held up to the end, but not much more. There is no noticeable oil that's accumulated in the PCV hose, and no oil spots in the driveway underneath where it vents. So I wouldn't say I have a blowby or sealing problem, just curious if there's a performance or longevity benefit to going with a catch can.

 

[Dougal]

It saves a hell of a lot of mess. The fog you get from the breather on even a healthy engine is amazing.

It also removes an entry point for moisture and dust when offroad.

 

[Feistl]

Yep, catch can either way, but you can either plumb it back into the intake or plumb it into the exhaust (there is a special fitting that uses the flow of exhaust gas to “suck” the vapour through. Biggest advantage is it stops the smell and oil mist getting over everything in the engine bay and burns it out the exhaust.