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Discussion Starter #1
The more I read about vaccum leaks and so forth I came across a thread stating that if you ran a breather in each valve cover you could plug the pcv valve. What I have may be creating my idle problem or maybe not, I thought I'd atleast ask. I have a set of Trick Flow valve covers and the drivers side has a breather hole cut out so I put ina breather. The passengers side has two holes in it, a hole near where the throttle bracket is for another breather so I just put a low profile chrome cap and the second near the front that I used for the oil fill tube. So basicly I have 3 holes in my valve covers one with a breather one with a oil fill plug and one with a oil fill tube and plus I'm runnin the original pcv setup from the upper intake to the hole in the rear of the lower manifold with a screen. What do I need to do, plug the 3 holes, plug 2 and leave one for oil fill tube, or plug the pcv at the upper intake???
 

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you might replace the oil filler neck with another breather??????
 

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Discussion Starter #3
But I thought I read somewhere that you can't run both, breathers and a pcv valve, maybe I'm wrong???
 

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You shouldn't run both a breather and a PCV since this equates to a 3/8" vacuum leak...

Block off the PCV or block off the breathers.
 

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Discussion Starter #5
Thanks ryan, I knew you would straighten it out, thanks again for all your help!!
 

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Alternatively you can run a breather hooked to a check valve that only lets gases out and nothing in. that way when you really need the breather (when you have positive crank case pressure) it will let gas and vapor out, but under normal driving conditions it will not let unmetered air in and back to the PCV.
 

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Alternatively you can run a breather hooked to a check valve that only lets gases out and nothing in. that way when you really need the breather (when you have positive crank case pressure) it will let gas and vapor out, but under normal driving conditions it will not let unmetered air in and back to the PCV.
LOL, I made a very similar rig but took it off. I used the biggest size PCV valve I could find for the check valve (which was not much bigger than the average PCV really). I haven't seen any one else doing that so I figured it was a dumb idea ;)
 

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Actually it is really common for boosted applications. The reason is, under boost there is no vacuum for the PCV to operate. If you don't have a breather, you can blow seals and blow the dipstick out of the tube. However, if you run a breather and a PCV you run into the vacuum sucking air from the breather.

USPlastics sells inexpensive liquid gas check valves up to 3/8" in diameter.

Plastic Tanks, Plastic Buckets, Plastic Bottles, Labware, PVC Pipe - United States Plastic Corporation ®

I'm currently using them in m procharger buildup.
 

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Okay, sounds interesting, I have the stock valve covers with the vent hole in passenger fill tube (that is currently plugged off because I have a breather), you think that roughly 5/32-9/32 hole would be large enough to vent off the pressure through such a rig? I could create my own 3/8 or larger hole and install fittings if needed. Ideally, I'd have vents in both covers but I don't.
 

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Okay, sounds interesting, I have the stock valve covers with the vent hole in passenger fill tube (that is currently plugged off because I have a breather), you think that roughly 5/32-9/32 hole would be large enough to vent off the pressure through such a rig? I could create my own 3/8 or larger hole and install fittings if needed. Ideally, I'd have vents in both covers but I don't.
I don't know, the hole on my stock valve covers was 3/8". I have a piece of 3/8" hose going to a filter and then a check valve, then it runs to the inlet side of my procharger.
 
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