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ive noticed that most subys with cold air intakes still reatache there breather hoses to the new pipe.

now what i was think is, wouldnt this just send hot air in to the intake pipe
(just what were all trying to avoid) i am talking about my '92 ej20 N/A engine though so no i/c just straight to the throttle body.

maybe someone needs to fill me in on how these breathers work ?
because from what i see it would better to leave these out of the intake pipe and just give them there own filters (and maybe even intake to bring dome the engine temp ????

lets talk

http://www.fram.com/

PCV- The heart of your vehicle's Pollution Control System
The PCV valve is an important part of the engine even though it may not look it. PCV stands for Positive Crankcase Ventilation. The PCV valve was the first of the emission system components to be put into production vehicles. Critical to Emissions Compliance Testing, FRAM PCV Valves can help ensure that your vehicle meets the Emissions Standards. Regular maintenance helps avoid poor engine performance, rough idling and stalling.

Although the PCV valve is a simple device, it is designed to reduce the air pressure inside the engine and redirect it to the air intake system. Since the air is contaminated with oil, gasoline and engine metal residue, this in time will affect the operation of the valve assembly. The valve can plug up over time, which will result in a poor running engine that delivers less power and reduced fuel economy.

It is good maintenance to check and even replace the PCV valve in your vehicle every 30,000 miles (50,000 kms). It is a simple and inexpensive repair that will help contribute to a fuel-efficient and smooth running engine.


It's such a minute amount of air, it won't make a difference. If you really are concerned with it, then just plug the hole on your intake tract and vent the PCV valve to the air. With or without a filter. Doesn't matter.

J-MoNeY wrote: It's such a minute amount of air, it won't make a difference. If you really are concerned with it, then just plug the hole on your intake tract and vent the PCV valve to the air. With or without a filter. Doesn't matter.

I disagree.

It makes a difference for idling. and it helps lean out the mixture a small bit (the MAF isn't picking up on that extra air). I stuck my finger on the valve when my dad was revving around 3k, and there is a lot of suction on that little sucker.

but, that's not the main reason I disagree:

DO NOT VENT TO ATMOSPHERE. A buddy of mine over on SLi did this, and he almost died, because he was falling asleep at the wheel. The carbon monoxide and stuff was hanging in the engine bay during city driving, and he was inhaling it from his HVAC system. So if you do decide to vent, vent out of reach of the HVAC intake.

Was that the one i read about on Nasioc a couple days ago?

Plays_With_Toys wrote it up, yes, he's the one.

wiscon_mark wrote: I disagree.

It makes a difference for idling. and it helps lean out the mixture a small bit (the MAF isn't picking up on that extra air). I stuck my finger on the valve when my dad was revving around 3k, and there is a lot of suction on that little sucker.

but, that's not the main reason I disagree:

DO NOT VENT TO ATMOSPHERE. A buddy of mine over on SLi did this, and he almost died, because he was falling asleep at the wheel. The carbon monoxide and stuff was hanging in the engine bay during city driving, and he was inhaling it from his HVAC system. So if you do decide to vent, vent out of reach of the HVAC intake.

+1

My dads 87 carbed bronco had and air pump seize up on him so we just removed it and capped everything off. It's has an extremely strong gas smell coming from it and I wouldn't attempt lighting a match anywhere near it. It will give you a headache driving it around with the windows up. We drive it with windows down, during summer not so bad since the a/c doesn't work, in the winter though heater is on full blast, once it warms up.

got to love the raw hydrocarbons
hope I don't get a cancer...

I'd be more worried about getting Carbon Monoxide poisoning, and falling asleep at the wheel....tis a scary thought Why don't you just get a silicone hose and vent it out of the engine bay?

You guys that are for the PCV all bring up good points, but the reason anyone wants to do this is because they think it will increase performance. The truth is though, that it will decrease performance. PVC, beeing a positive ventalation system creates a small amount of vaccuum in the crankcase. What this does it reduce pumping losses as the crank and pistons need to move less air in the crankcase when they spin (remember the back of the piston moves just as much air as the top does). PCV also promotes ring sealing as it helps to hold the rings to the bottom of the ringlands. You'll notice that any race car that runs a wet sump system will have some sort of PCV (either to the intake or the exhaust). Dry sump cars don't need them as the sump pump creates quite a bit of vaccuum on its own. You'll never see it vented to atmosphere.

So, having PCV is good for performance and helps the enviornment.

No PCV is a possable health hazzard, can make your engine bay messy, is bad for performance, bad for the enviornment and is illegal (it's a federal crime to remove any emissions device from a vehicle operated on public roads per the Clean Air Act).

There's the pros and cons... you make the choice.

very nice info. I'll post it on SLi when I get one there

quoting you of course

ive seen a guy with a 240sx SR20DET swap who put a little filter on his pcv valve. it was leaking oil out of it.

I pulled a dumba$$ manuever tonight. I am trying to reroute the pcv lines correctly and I hooked up something backwords. End result a giant cloud that consumed my car and the neighborhood apartment complex. i figured it out now however.

Maybe you let the smoke out of the wires as well

Remember, all engines are run by smoke, if you let all the smoke out, they don't work anymore!


But seriously folks....

Install a catchcan of somesorts on the breather tubes. With a filter if possible.

This is because the less oil contaminated air you reintroduce into the intake, the MUCH LESS chance of deadly detonation you have. Oil in the air SERIOUSLY reduces octane levels. I know. I blew shit apart. Now that I have a weird ass catch can and filter, I am suffering much less det and I suspect this is a portion of why I am running so much better.

you have picks of your setup douglass?

No, "my" camera has been taken back my its owner, my brother.

But What I have is an pnuematic air filter inline right before it hits the supercharger.

Other than the stupidity of having a glass catch can, it seems to do its job.

Its hooked up basically right before the lines would normally go back into the systems, whatever they may be.

Doug,

If I meet up with you next week, I can take a few pics. I'll plan to bring my camera.

hey josh, do you have pictures now?

Looks like you found it, but here's the pics

http://bbs.legacycentral.org/viewtopic.php?t=24286

I was asking more for others benefit