is this correct? PCV?
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From: Orange County, CALIFORNIACATIONATED, USA
is this correct? PCV?
<FONT SIZE="2"><FONT COLOR="darkred">-=From Team-Integra.net=-</FONT></FONT>
- Are breather filters really bad?
Yes they are. Read further for why.
"Here's the stock PCV diagram from the Helms manual. On the left is a cutaway view of the engine. On the right is a cutaway view of the stock intake. In the middle are the separate breather circuit and the PCV valve circuit:
(Picture of a Big Red <FONT COLOR="red">X</FONT>)
all you have to learn is how the fresh air cicuit flows (follow the open white arrow) and how the crankcase vapor (with oil vapors in it ) circuit flows (follow the black arrows). Notice which circuit flows to the valve cover (on top of the engine on the left)....it's NOT the crankcase vapors. When you add a breather, you remove the line from the intake to the valve cover.
The honda crankcase breather is a POSITIVE pressure ventilation system.The air from the intake blows into the valve cover. It is NOT a negative pressure ventilation system...it does NOT suck air from the valvecover to the intake.
Breathers remove the source of positive ventilation that repressurizes the POSTIVE CRANKCASE VENTILATION (PCV) valve.
There is less pressure in the crank when you add a breather at the valve cover. The consequence of this is you get more positive blow-by from the combustion chamber past the piston rings and into the crankcase. More blow-by means less cylinder pressure...less cylinder pressure means the burn is slower and less complete...the result is more emissions and less power.
If you want to do this right and remove oil vapor from the circulating crankcase before it goes into the intake valve then, get an oilcatch can and put a breather on the catch can. Then place the catch can in between the valve cover breather and the PCV valve.
Disconnecting the breather tube, which blows fresh intake air into the valve cover, and placing a breather on the valve cover just creates more blow-by and emissions. Eventually you have so much blow-by, you lose power.
----------------------------------------------------------------------------
Me: I dont get how the intake is suppose to blow air into the valvecover when on a NA car the intake is a Vaccume...? Did the guys at T-I.net mess up???
- Are breather filters really bad?
Yes they are. Read further for why.
"Here's the stock PCV diagram from the Helms manual. On the left is a cutaway view of the engine. On the right is a cutaway view of the stock intake. In the middle are the separate breather circuit and the PCV valve circuit:
(Picture of a Big Red <FONT COLOR="red">X</FONT>)
all you have to learn is how the fresh air cicuit flows (follow the open white arrow) and how the crankcase vapor (with oil vapors in it ) circuit flows (follow the black arrows). Notice which circuit flows to the valve cover (on top of the engine on the left)....it's NOT the crankcase vapors. When you add a breather, you remove the line from the intake to the valve cover.
The honda crankcase breather is a POSITIVE pressure ventilation system.The air from the intake blows into the valve cover. It is NOT a negative pressure ventilation system...it does NOT suck air from the valvecover to the intake.
Breathers remove the source of positive ventilation that repressurizes the POSTIVE CRANKCASE VENTILATION (PCV) valve.
There is less pressure in the crank when you add a breather at the valve cover. The consequence of this is you get more positive blow-by from the combustion chamber past the piston rings and into the crankcase. More blow-by means less cylinder pressure...less cylinder pressure means the burn is slower and less complete...the result is more emissions and less power.
If you want to do this right and remove oil vapor from the circulating crankcase before it goes into the intake valve then, get an oilcatch can and put a breather on the catch can. Then place the catch can in between the valve cover breather and the PCV valve.
Disconnecting the breather tube, which blows fresh intake air into the valve cover, and placing a breather on the valve cover just creates more blow-by and emissions. Eventually you have so much blow-by, you lose power.
----------------------------------------------------------------------------
Me: I dont get how the intake is suppose to blow air into the valvecover when on a NA car the intake is a Vaccume...? Did the guys at T-I.net mess up???
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Re: is this correct? PCV? (10K2HVN)
it DOES NOT blow air into the valvecover,it sucks the vapors out and into the intake and then burned up,for emissions reasons..Obviously whoever wrote that article never bothered to look under his hood,disconnect the pcv and looked 
Thread Starter
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From: Orange County, CALIFORNIACATIONATED, USA
Re: is this correct? PCV? (D-Man)
hmmm..maybe if their picture worked then maybe we would get-it a little bit easier....but i think i get where hes coming from...
Theres 2 tubes that lead to the engine:
-One that goes from the Intake Tube to the Valve Cover (before the Throttle Body).
-And one that goes from the Crank Case (block) to the Intake Manifold (after the TB)
..when the TB is closed then the vacuum in the IM will cause a flow that goes from the Intake to the Valvecover to the Block through PCV into the IM...! Therefore Supporting the statement that the air flows from the Intake to the Valvecover..! Make sense??? ..but is it really like that..im just trying to justify that statement....
Theres 2 tubes that lead to the engine:
-One that goes from the Intake Tube to the Valve Cover (before the Throttle Body).
-And one that goes from the Crank Case (block) to the Intake Manifold (after the TB)
..when the TB is closed then the vacuum in the IM will cause a flow that goes from the Intake to the Valvecover to the Block through PCV into the IM...! Therefore Supporting the statement that the air flows from the Intake to the Valvecover..! Make sense??? ..but is it really like that..im just trying to justify that statement....
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Re: is this correct? PCV? (10K2HVN)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 10K2HVN »</TD></TR><TR><TD CLASS="quote">...but is it really like that..im just trying to justify that statement....</TD></TR></TABLE>
Yes it really is like that. I don't like the wording of that article, because all cars have PCV of one kind or another. The word 'positive' doesn't mean above atmospheric pressure; it means more like 'certain' or 'guaranteed'.
The PCV line is on the valve cover of my Accord, but it's on the breather box on the back of the block in my Integra. But it does the same thing either way - it sucks air OUT of the engine. Either way, those baffles are supposed to catch oil & return it to the engine. A catch can on that line just catches whatever gets through the factory catcher.
The breather hose that goes to the intake allows clean air to be drawn INTO the engine to make up for what's sucked out. If your PCV valve is plugged, or if you have a lot of blowby, then it overwhelms the PCV valve & flows out through the breather line. That's how you get oil in your intake tube. A catch can in this line isn't needed unless you have more blow-by than the PCV valve can handle.
Yes it really is like that. I don't like the wording of that article, because all cars have PCV of one kind or another. The word 'positive' doesn't mean above atmospheric pressure; it means more like 'certain' or 'guaranteed'.
The PCV line is on the valve cover of my Accord, but it's on the breather box on the back of the block in my Integra. But it does the same thing either way - it sucks air OUT of the engine. Either way, those baffles are supposed to catch oil & return it to the engine. A catch can on that line just catches whatever gets through the factory catcher.
The breather hose that goes to the intake allows clean air to be drawn INTO the engine to make up for what's sucked out. If your PCV valve is plugged, or if you have a lot of blowby, then it overwhelms the PCV valve & flows out through the breather line. That's how you get oil in your intake tube. A catch can in this line isn't needed unless you have more blow-by than the PCV valve can handle.
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From: Nowhere, USA, USA
Re: is this correct? PCV? (10K2HVN)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 10K2HVN »</TD></TR><TR><TD CLASS="quote">
..when the TB is closed then the vacuum in the IM will cause a flow that goes from the Intake to the Valvecover to the Block through PCV into the IM...! Therefore Supporting the statement that the air flows from the Intake to the Valvecover!
</TD></TR></TABLE>
Yes..its being sucked thru by the PCV
..when the TB is closed then the vacuum in the IM will cause a flow that goes from the Intake to the Valvecover to the Block through PCV into the IM...! Therefore Supporting the statement that the air flows from the Intake to the Valvecover!
</TD></TR></TABLE>
Yes..its being sucked thru by the PCV
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