Thread: How do you choose the correct PCV valve?

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Originally Posted by joeybsyc

Does it matter if the PCV valve is actually "in" the valve cover? I have one of those "breather looking" push in deals with the tube out the side.. I call it this because although it looks like a breather, there are no holed in the bottom of it like a standard push-in breather has, just the tube coming out the side and a solid bottom. i have a hose connected to the tube, and a PCV inline between the valve cover and the carb... seems to work, but i still get a little oil that seeps around the breather.

No.

Here's mine sitting on top of an oil/air separator I made.
An SBC PVC fwiw, one of the performance models.

Look inside the PVC if you can, you'll see a number which correlates to the opening vacuum level.

The angle on the drain/return hose was changed so residual oil would drain back by gravity.

And a pic of a couple of the home-made fittings I made that go in the Buick's PVC grommet on the intake manifold.
The 90 degree model was used so the drain/return hose would run downhill.
The PCV in the pic with the fittings is a stock 455 Buick.

The straight one required the hose be curved and that sat it up too high fr proper drainback.

Originally Posted by C9x

No.
Look inside the PVC if you can, you'll see a number which correlates to the opening vacuum level.

Where should the PCV open in relation to idle vacuum?

That was good reading, thanks for the link. I think I have it working now.