Pcv or not to pcv?

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82sbshortbed

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I've just got 2 breathers on my valve covers on the BBC. Should I put a pcv Value on driver's side valve cover? Is there an advantage to running one? I have a brand new one on the 305 that I could pop right in. Just wondering.
 
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TX87R10

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I've just got 2 breathers on my valve covers on the BBC. Should I put a pvc Value on driver's side valve cover? Is there an advantage to running one? I have a brand new one on the 305 that I could pop right in. Just wondering.

Personally I would use a PCV valve instead it will probably fit better... (jk had to be a smart ass)
 

Vbb199

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Let that motor breath!
 

Itali83

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I just have a breather on each valve cover of my 350. Old school. It slobbers a bit on the valve cover but I’d rather not have my motor eat it’s own ****. I grew up and still have many old school diesels in our big rigs and all vent blow-by out a vent so my 350 does too.

ben
 

Shorty81

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Not sure if this is correct but... I always installed mine on the passenger side valve cover because of rotation. Current bbc is very happy that way with no vapors detected inside cab. Hose connected to intake.
 

jake wells

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PCV is a metered vacuum leak so you decide what you want to do.
 

Turbo4whl

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PCV is a metered vacuum leak so you decide what you want to do.

Jake is correct. If your carb was ported for PCV, all kinds of tuning issues without it. Or are you running a pre 1968 carb?
 
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Rusty Nail

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Your carburetor wants that vapor.
I doubt it will ever tune correctly with that port plugged.
Huge difference between the driver side and passenger side cylinder head...damn. One blows and one sucks yes?

Yes.

* I dont know anything about big blocks though...
 

Ricko1966

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PCV was implemented for a reason it gets the water vapors from condensation ,damp air, whatever out of the crankcase.I'd run it,pull the oil cap off a pre 68 car that nasty yellow accumulation is water vapor mixed with oil vapor
 

jake wells

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PCV was implemented for a reason it gets the water vapors from condensation ,damp air, whatever out of the crankcase.I'd run it,pull the oil cap off a pre 68 car that nasty yellow accumulation is water vapor mixed with oil vapor
i would personally leave it alone since one that is working fine won't cause any harm.
 

Curt

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In my my mind the issue still isn’t solved.

I will say I did a fair amount research online when I was setting up my system.

I found way more engine pros recommend a PCV valve.And just like Shorty noted on the passenger side.

I think you’re on your own here.Good luck!
 

75gmck25

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Engines without PCV have a road draft tube to let passing air draw vapor out of the crankcase, and I doubt you have that on your engine unless you installed a very early SBC. In simple terms, venting the crankcase is not a new emissions setup; Chevy has been doing it for many years.

Your engine will suffer if you don’t have a PCV.

Bruce
 

Bennyt

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PCV. An adjustable one is preferable if you can't find the exact one for your set-up. The parts stores are all universal with 1-2 part numbers but that's not how they left the factory. GM probably had 20+ different PCV's for SB and BB tuned to application.
 

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