PCV orientation
Thread Starter
Racer
Joined: Feb 2012
Posts: 421
Likes: 27
From: Harrisburg PA
PCV orientation
I have ALWAYS put the PCV valve in the driver's side valve cover, and a breather or air cleaner tube in the passenger side.
I have seen several photos of late with the valve in the pass side, and breather in the driver's side...
Will it work either way, or is the latter configuration incorrect?
I have seen several photos of late with the valve in the pass side, and breather in the driver's side...
Will it work either way, or is the latter configuration incorrect?
Race Director
Joined: Sep 1999
Posts: 11,360
Likes: 382
From: Plano TX
It works either way. All you're trying to do is getting a flow of air from one valve cover, down through the lifter valley and crank case, and out the other valve cover. The direction is not important.
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
There is a small difference because of the rotational direction of the crankshaft which is why it was placed on the drivers side but I doubt it really matters that much, if at all. It is a little higher pressure area because of that so I guess they just used that side but either will work.
Last edited by CanadaGrant; Oct 13, 2017 at 11:44 PM.
Pro
Joined: Sep 2017
Posts: 516
Likes: 72
From: Modesto California
I remember seeing Mopars that had their PCV in the lifter valley cover under their intake manifold. You DO remember lifter valley covers, don't you? For a long time only Chevrolet had intake manifolds that sealed the lifter valley and thus eliminated an additional part and an additional gasket. A brilliant idea in the mid 1950's.
Tech Contributor
Joined: Aug 1999
Posts: 14,370
Likes: 6,361
From: At my Bar drinking and wrenching in Lafayette Colorado
There is a small difference because of the rotational direction of the crankshaft which is why it was placed on the drivers side but I doubt it really matters that much, if at all. It is a little higher pressure area because of that so I guess they just used that side but either will work.
That's correct.
Lars
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
The only reason to actually care about which side it is on is if you live in a state which has strict emissions control requirements. They may be really 'sticky' about the emission components being on the car EXACTLY as it came from the factory.
Functionally, it makes very little difference...as long as you have carb inlet source going to one valve cover and the PCV valve on the other side.
Functionally, it makes very little difference...as long as you have carb inlet source going to one valve cover and the PCV valve on the other side.
Pro
Joined: Sep 2017
Posts: 516
Likes: 72
From: Modesto California
The only reason to actually care about which side it is on is if you live in a state which has strict emissions control requirements. They may be really 'sticky' about the emission components being on the car EXACTLY as it came from the factory.
Functionally, it makes very little difference...as long as you have carb inlet source going to one valve cover and the PCV valve on the other side.
Functionally, it makes very little difference...as long as you have carb inlet source going to one valve cover and the PCV valve on the other side.
And as the inline 4 and 6 cylinder engines don't have a "side" that makes matters even more confusing.
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Melting Slicks
Joined: Sep 2016
Posts: 2,191
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From: Wauconda IL
I remember seeing Mopars that had their PCV in the lifter valley cover under their intake manifold. You DO remember lifter valley covers, don't you? For a long time only Chevrolet had intake manifolds that sealed the lifter valley and thus eliminated an additional part and an additional gasket. A brilliant idea in the mid 1950's.
Pontiac V/8's in 60's and 70's also had valley covers with the PCV stuck in them.
Burning Brakes
Joined: Jan 2007
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From: Lighthouse Point FL
Melting Slicks
Joined: Sep 2016
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From: Wauconda IL
Race Director
Joined: May 2006
Posts: 18,660
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picture above has replaced the stock breather pipe coming from the passenger valve cover to the air cleaner with a valve cover breather cap. You can still see the hole in the side of the air cleaner assembly where the stock pipe connected.
Team Owner
Joined: Sep 2006
Posts: 31,168
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From: Westminster Maryland
Hi Keith,
This widely circulated drawing seems to imply the direction of rotation has an impact… but I don't see how it can be very much of an impact since the blow-by gasses are coming from each side of the block.
Regards,
Alan
This widely circulated drawing seems to imply the direction of rotation has an impact… but I don't see how it can be very much of an impact since the blow-by gasses are coming from each side of the block.
Regards,
Alan