hey guys, i wanna put an air breather on my vavle cover but i don’t know what to do with the hoses that go from the vavle cover-intake and valve cover-below distributor. Can you guys help me figure out what to do if you have done it, i have a 91 rs THANKS for the helpP.S. I have a couple of blue vacum hoses left over from air intake installation 
Why would you want to do that unless you’re running boost?
That is your PCV Valve breather tube. It does not pull air from your intake into the engine, it actually pulls air from the engine into the intake so that it can be burned through the combustion chamber.
Also, putting breather on the PCV Valve and taking away the vaccume for your PCV Valve will shorten the life of your piston rings, loosing performance and ultamitally killing your engine.
Don’t do it.
-Steve
not to mention automatically faling emissions… if you have it…
DAY U IZ you are confused man. The pcv valve is in the intake manifold not the valvecover.
The area in question is an air intake into the head. The pcv is where the fumes from the motor are ran back into the intake manifold to be burned in cumbustion. This also adds to possibility of detonation. This is where people use the catch can to collect the oil vapor so it does not get sent back into the motor.
Tinytorr the little air filters are a very bad thing.
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:
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.
This is from Team Integra’s site.
NC-B17A: Nice write up on what a PCV system is and how it works…too bad your pics wont load:(
I could be wrong about where the PCV Valve is, but I think I’m right because if the tube comes from the valve cover to the intake tube, why put the valve in the manifold where all the other intake air is moving around?
Get your pictures to load up, I’m anxious to find out for sure.
-Steve
Originally posted by NC-B17A
[B]
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.
[/B]
Huh? Put a “breather” on the catch can? Why? Put the catch can between the the valve cover “breather” and the PCV valve? Huh? You mean put the can between the crank case PCV exit and where the PCV enters the intake manifold I think…
NO! (slaps you on the wrist)
DAY U IZ the pcv valve is mounted to the IM it is not hooked to the valvecover
Haberdasher I copied that from Team-Integra’s site you can use a breather on the top of the catch can if you are not worried about the enviroment. I would not do this on my own car I would leave it as an closed system. I will take very detailed pics when I put a catch can on my car.
Originally posted by NC-B17A
[B]
Haberdasher I copied that from Team-Integra’s site you can use a breather on the top of the catch can if you are not worried about the enviroment. I would not do this on my own car I would leave it as an closed system. I will take very detailed pics when I put a catch can on my car. [/B]
Incorrect…It has to be a closed system or it will not work. Air isn’t going to flow into the valve cover PCV inlet by virtue of their just being a hole their for air to go into. There has to be a displacement of air somewhere else in the system. That’s why the system needs to exit to a vacuum, and that’s why it can’t exit to atmospheric pressure. The PCV system has to have a vacuum on it, that’s why you need a PCV valve and that’s why it’s plumbed to the intake manifold on a stock PCV system. If you are putting a catch can into the system you have to plumb it as I have plumbed it on my car with the PCV valve on top of the can and connecting it to a vacuum source.
oh
archivethis
I remember reading that there is a way to put a breather on the catch can. But I would not do that anyway.
so you are basically saying that having a tube going from the valve cover to the intake piping gives a better performance than just having a breather attach to the valve cover for the Postivie crank pressure… is that correct?? if so i’m going to go buy a tube tomorrow, the reason i do’nt have mine sotck hose is a tad bit too sure and i got the ICEMAN CAI used and did not come with the pipe.