PCV Valve

[mrtleavitt]

Is one pcv valve the same as any pcv valve? I want a pcv valve that has a built in 90 degree turn. The original one has the straight up fitting which goes to make a big ugly loop before it goes back down to the intake. At Autozone there was a 90 degree pcv valve right next to the straight one for my 390 and I was wondering if any harm would be done if I used the other one?

[fordman]

i dont know for sure. buti want to say that they are all the same except for the outside size of them.

[knightfire83]

I didn't know either, but a quick trip around the internet says:

That they are all generally the same design, but flow at different rates. A 4 cylinder version will flow less than a 8 version.

Keeping that in mind, if you were to get one from the same class of engine 4/6/8cyl and in the general area of cubic inches they would all be presumably interchangeable.

I think the one I'm running on my 360 was intended for a 350 Che*y with the 90* plastic elbow on it.

GM / Cadillac division first invented the PCV system during WWII for use on tanks that couldn't use the road draft version of venting the crankcase while forwarding rivers and streams because water would enter the engine.

In the 1960's GM gave the PCV system to all the US auto makers royalty free because it was proven to dramatically reduce hydrocarbon emissions in automobiles.

Most diesel engines don't use a PCV system, but use the road draft system which dumps the crank case vapors to the atmosphere.

[fordman]

Most diesel engines don't use a PCV system, but use the road draft system which dumps the crank case vapors to the atmosphere.

can you say detroit diesel? drip drip drip.