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Hi Guys....I have a PCV valve on one valve cover and a breather on the other. I also have a breather as part of the cap on the oil fill tube at the front of the intake manifold. Question is should I find a way to cap the oil tube with either a non breathing cap or some other trick? I don't know if two breathers is one too many or if it really doesn't matter? If I should cap the fill pipe has anyone seen a non breathing cap or anybody have any tricks to make the breather cap into a non vented cap? This is a primarily stock 350 and the PCV is tied to the base of the carb. Thanks
 

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I don't think "too" many breathers can hurt (unless they're blowing oil from lack of baffling. I certainly would not block the filler tube one as that would provide air to the lifter valley and crankcase. The valve cover breathers are more prone to blowing oil with poor baffling whereas the one on front of intake is less prone. When the engine is shut off the extra breathers will allow fumes to exit the crankcase.. Just my experience.

(Only problem would be if NC smog inspection has a problem with open breathers, I know Buncombe County has inspections)
 

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1969 Chevelle 2 Door Sport Coupe Malibu COPO clone
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:cool: Unless you're doing serious racing, why not keep the factory PCV system? Crankcase gasses are bad.
 

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Pcv system keep pcv valve on one cover and 1 fresh air Intake on other valve cover that way it pulls air thru out entire motor not just valve cover to under intake.. don't need more breathers if you did you would hear air being sucked in thru seals etc your good..

If you are computer controlled attach the fresh side to the intake tube after mass air flow so you do not get any lean codes or issues
 

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I don't think "too" many breathers can hurt (unless they're blowing oil from lack of baffling. I certainly would not block the filler tube one as that would provide air to the lifter valley and crankcase. The valve cover breathers are more prone to blowing oil with poor baffling whereas the one on front of intake is less prone. When the engine is shut off the extra breathers will allow fumes to exit the crankcase.. Just my experience.

(Only problem would be if NC smog inspection has a problem with open breathers, I know Buncombe County has inspections)
brrather will not puke anything with a proper pcv system if you have not pcv system you will have puking oil every where. It's installed from factories for the same reason
 

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The extra breather won't affect the PCV system in any way that's bad because the amount of vapors that's recirculated is controlled by the size of the orifice inside the PCV along with the pintle (or whatever its called ?) and the springs tension.
https://torquepost.files.wordpress.com/2013/05/pcv.gif
Simple but effective.
 
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