While installing my valve covers (stock for Vortec trucks) last night I noticed something odd.  The valve covers only go on the heads one way, but when installed that way the PCV hole on the drivers side is in back and the breather hole on passenger side is in front -- opposite of our cars' stock positions.  Again, I can't just install the other way (breather apparatus interferes with a rocker) and swapping them between heads does not solve the issue, it would just move the oil fill over to the passenger side.   Is this an expected scenario?  I think the PCV should not be a big problem - just need to run a longer hose - and perhaps the same thing with the breather.  (I'm using my stock air cleaner base so I had hoped to use the original breather pipe, but I'll have to re-engineer that, I guess)   Any thoughts?  I'm guessing most folks with Vortecs don't use the original air cleaner base so they don't worry about that.  But the PCV I'm wondering how others do it - longer hose or can you run PCV from a port on the back of a Q-Jet?  Thanks guys....I'm making some progress.

|UPDATED|4/29/2012 7:10:32 PM (AZT)|/UPDATED|

Is this better?  I thought using a cell phone pic would automatically be small - no such luck.  Still had to convert to smaller size.  Sorry.

Ideally, the PCV valve and the breather would be at the front of the engine on both sides. That just ain't always how it works out, tho. I don't understand why the breather baffle on the one valve cover would hit with it on one head, but not on the other head. I guess it's one of those things you'd just have to see.
You'll just need to reroute the hoses, apparently. May not look "stock", but then again...neither will the center bolt valve covers.

Joel, just to clarify - the valve covers are identical except that one has the oil fill and the other has a round flat spot (where I mounted the emblem) in the same location.  So both fit on either head, but neither of them can be inverted (front to back).  This is kind of a hard one to explain with words.  But anyway, the short description is they can only be installed one way and that puts both small holes in the opposite location of where I was expecting.  What did you mean about how it is preferred to have the breather in the front?  I just checked my air cleaner (had to make sure my memory wasn't going) and with the stock pipe it definitely hooks in to the pass side valve cover at the back.  

What I said was "Ideally"....in the real world, it rarely happens! Having the breather and the PCV at the front keeps either of them from sucking up as much oil vapor. I unnerstand now what you said aboot them not flipping. I thought you said they would only fit on ONE head each. 

Be carefull with those center bolt pressed steel covers, if you overtighten them they deform just enough to leak at the gaskets. I had problems with mine and changed them out for cast alumimum ones, no more leaks. Good luck.

Thanks Dave - I'll be sure not to over-tighten 'em.   They're just on there loose now - I was thinking 10-12 ft-lbs.  I'm using the thick fel-pros that you put on completely dry - maybe that will help.  

You'll usually find that the PCV valve will be at the front on one side, and the breather in the rear on the other, but they could be either way. The idea is to get the oil vapor/blowby completely out of the crankcase. The PCV and breather in the same valve cover only clears the one valve cover area, so that isn't done by any manufacturer, but I've seen folks do that themselves, for whatever reason. By putting the two components on opposite sides, it draws the blowby thru the entire crankcase, doing a much better job of clearing the vapors. 

I have a ZZR in my '78. This spring I swapped outthe valve covers (again...I wanted something else).  I went with some polished billet aluminum and of course they are center-bolt (by the way, chevy does make an adapter to use on center-bolt situations where you can use the standard vavle covers instead of center-bolt).  The Breather/oil fill is on the passenger side towards the rear and the breather/PCV is on the drivers side towards the front.  It has been so long ago that I removed the L-82, that I do not remember the stock position.