# pcv to air breather



## machine23 (Oct 3, 2007)

anyone know what happens to your smog compliance if you replace the pcv valve with a breather filter instead?


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## OchnofConcrete (Jan 7, 2008)

a pcv... is a positive crankcase valve.... exactly what it says!

positive=positive air pressure
crankcase=in the part where the oil is
valve=is only supposed to go one way and be turned on and off when the engine needs it.

here's how it works...

vacuum is created when you crank an engine by the pistons sucking air in.... called the intake turn.
a tube goes from the intake tube BEFORE the throttle and into the valve cover...
only other opening to the oil is a valve that only allow air to flow one way...

that's the pcv

then that is routed to the intake manifold right before the head... *right before it's burned off*

basically... the vacuum of the engine pulls air through that route pulling the excess internal engine fumes *all it is is emissions and helping oil last longer*

if you don't have a valve. instead have a filter... a possible back pressure can occur pushing air the other way through the routing and just like having a closed system... it will eventually push oil out through the in.......
literally eventually pushing oil into to the air intake tubing RIGHT BEFORE THE THROTTLE BODY.

and that will gum up your throttle, vacuum tubes, intake, and eventually your engine.

any other questions?


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## nickz3188 (Sep 27, 2007)

you can stick a filter on the pcv valve...


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## machine23 (Oct 3, 2007)

dude im not an idiot with cars. i know what the pcv does. ive seen other cars with the breather on it instead of a pcv. im just not sure if smog is too strict these days to allow that


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## nickz3188 (Sep 27, 2007)

if you did what i said and just hooked a filter up to your pcv valve it shouldnt really do anything, it just looks good, it just takes away a vacuum line, which comes from after your air filter anyways, so it shouldnt really do anything


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## machine23 (Oct 3, 2007)

yeah i know and understand what you were saying..a blue aftermaket filter would look nice


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## nickz3188 (Sep 27, 2007)

thats what i had on mine before i pulled my engine out, and it'll go back on when i put it back in


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## OchnofConcrete (Jan 7, 2008)

i did say it's just for emissions didn't i?


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## nickz3188 (Sep 27, 2007)

you did, but it looks better in my opinion to have a shinny filter on it rather than a vacuum line


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## OchnofConcrete (Jan 7, 2008)

*shrugs* i'd love to get to the asthetics of my car... unfortunately, i'm still in the full-on mechanics mode.

just put together a car from bare chassis in 4 days. woot. *tired*

that and i like to keep things OEM until i'm able to switch out entire systems together.. and i promised myself i wouldn't spend money on small parts til the biggies are out of the way... like modding an engine's compression/fuel/air ratio. sh!t's expensive. and i put stuff on all at once unlike the guys that throw on a cam and wonder why they lose half their power and blow up their engine.


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## nickz3188 (Sep 27, 2007)

i have an entire vg30et sitting in my garage, along with half a vg30e, everyting but the block, which is still hooked up to my transmission...it's not a daily driver so i can take all te time i want, which is nice, i'm still looking for a crossmember before i can put it in, but even before that i'm gonna take the turbo engine apart, powder coat most of it, and port and polish it all, so it's gonna take me a while


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## OchnofConcrete (Jan 7, 2008)

that's the only way to do it man... nice and maticulous. not always slow, but damn nice and maticulous. lol. sounds like you'll have a hella ride when your done. what's the chassis? i'm not real familiar with anything sides a KADE/SR/RB.... and a dodge 320 ;]


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## nickz3188 (Sep 27, 2007)

87 z31, and i'm pretty familiar with the ka24de, i used to have an altima, i love that engine, in 3 years it never gave me one problem


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## OchnofConcrete (Jan 7, 2008)

kewl. i love the classic nissans. i've always wanted a z car.... and i know it's sacriligis but i wanna drop a small block in it.

yeah, the other chassis i have was a freaking beast... it took everything i threw at it.. everything. only reason why it killed over was... lol, lets just say a woman messed with my head long enough/made me drive pissed off long enough/drove from CO Springs to Dallas and running around town trying to make a living long enough... for me to run out of oil. i was cussing myself out for weeks after my 3rd cylinder rod bearing melted on the crank and wore the crank to where i have to mig weld the crank and have it surfaced to be able to reuse that crank.

this one i just put together... was disassembled... and with minimal cash, was able to just clean all the grit and crap out of the engine, put it back together, and she's haulin ass on a rebuilt 180,000 mile car... ;] me proud of her.

but i's gots to take it easy on her til my first 1000mile oil change. it's hard... lol, after not getting to drive my 240 in a year and not drive at all since march.... it's really hard not to waste old mustangs. ;]


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