So this is the safest way to run PCV? [pics]

ChiGGz · Sep 19, 2006

Stole this from another post, but basically should I set it up like this but with an inline filter at the pressure relief tube (side)?

I'm running a GM-MAF after the turbo, so where should I place the other end of the pressure relief tube?

You must be logged in to view this image or video.

ChiGGz · Sep 19, 2006

To clarify, I'm talking about the one marked with a ?

fourreGsixty3 · Sep 19, 2006

What people will do is run the filter on the line off the valve cover to an oil catch can, then have another line go over to the intake pipe so it functions just like stock, but the oil is caught in the catch can, so it doesn't go into the intake pipe then to the turbo then junk up the IC.

Dustin

eldiabloz13 · Sep 19, 2006

Could have nothing on this pipe or anything to block it cause oil to spray all over the engine bay?

sheldon · Sep 19, 2006

This is how you do it.....detatch the the pcv valve line from your intake mani and run it to your catch can...Dont forget to plug your intake mani...then run your crank case vent to your catch can as well...best way!

fourreGsixty3 · Sep 19, 2006

eldiabloz13 said:
Could have nothing on this pipe or anything to block it cause oil to spray all over the engine bay?

This statement doesn't make much sense to me. If your asking if you can block it off...the awnser is no, the VC must breath, if you are asking if you can leave nothing on or just a filter on the little nipple, the awnser is Yes, both of those ways you can run, some people think that if you dont run with anything on it and vacuum occurs it might suck something inside the VC, Im not sure how likely this is, the other way is to put a small filter on it that looks like an air intake filter but really small, this will allow nothing to enter, but both of these will have that oil sprayed all over the engine bay. Project_tsi (Dan) just had the tube travel down to road level so it can drip any oil out that ###, and he capped the nipple that it went to on the intake pipe.

Dustin

MyBeatGSX · Sep 19, 2006

Here we go again...... :cry:

I have no pcv. The pcv is only for emissions. I have 2 hoses running off the valve cover, down past the transmission, and pointing at the ground. All the oil and fumes go out the hoses, onto the ground. No mess, no smell, no boost leaks, no catch cans, no complexity, no dirty intake, no dirty IC, no dirty piping, no problems. The end.

ChiGGz · Sep 19, 2006

, ya i dont want to start this debate up again.
Let me re-ask the question..

With a GM-MAF after the turbo, where do I hook up the side hose --before or after the GM MAF?
My guess would be before the turbo by the inlet? But wouldn't the sucking force air into the valve cover?

MyBeatGSX · Sep 20, 2006

If you insist on running that setup (which I hate, let that be known), then yes, hook it up pre-turbo in the intake pipe. You can also put another NON vented catch can on that hose to keep from blowing oil into the tank pipe. In fact its highly advisable that you do this, or you just wasted lots of time for nothing.

ChiGGz · Sep 20, 2006

MyBeatGSX said:
If you insist on running that setup (which I hate, let that be known), then yes, hook it up pre-turbo in the intake pipe. You can also put another NON vented catch can on that hose to keep from blowing oil into the tank pipe. In fact its highly advisable that you do this, or you just wasted lots of time for nothing.

Thanks for the input.
Out of curiosity, what is there to hate about this setup? The fact that it's a potential boost leak if the PCV fails?

fourreGsixty3 · Sep 20, 2006

MyBeatGSX said:
You can also put another NON vented catch can on that hose to keep from blowing oil into the tank pipe. In fact its highly advisable that you do this, or you just wasted lots of time for nothing.

I stated this one in my #3 post. Its the one I would go with...or the RRE catch can with the filter on top, or just run the line to the ground on the back side of the tranny, like you are doing Tyler. Actually I wouldnt go with it because I want as few lines in my engine bay as possible, so for me its either the RRE catch-can with venting, or the line to the ground.

Dustin

MyBeatGSX · Sep 20, 2006

IMO, the thing to hate is that the PCV remains in the car. I don't care whether anyone believes me or not, PCV is for EMISSIONS ONLY. There is no negative effect to taking it out. If you don't believe me, call Road Race Engineering because they agree with me.

There's a few issues here about why it should be eliminated...

Keep in mind, the boost leak is not 'potential', it is guaranteed. PCV valves leak, they all leak, its not even debatable. If it isn't leaking now, it will be next week. Pressurizing the crank case with boost is a very very bad thing.

It also makes your intake manifold, injectors, valves, combustions chamers, etc all filthy with oil and blow by crap. There is no need for this. Cars did without PCV for many many years until the government forced manufactuers to find a way to collect crank case vapors. I say again, it is for emissions only. Anyone that says contrary doesn't know or understand the history of federal emissions standards. And for all you tree huggers out there that are still running with a cat too, venting your crank case vapors into the atmosphere does not amount to a gnat pissing in the ocean, so don't sweat it.

Another issue is crank case ventilation under boost. At the moment you have a tiny hose to vent it through, that makes for lots of pressure in the crank case. If you run it how I have it, you now have 2 tiny hoses, that's double the venting you had before. Or you could go all out and put huge fittings on the valve cover and run 2 big hoses like lots of Supra and Skyline people do, I plan on doing this the first time I have a reason to take the valve cover off. This is good for the motor, it will love you for letting it breathe.

Take out your PCV and rejoice, for you have seen the light. LOL

fourreGsixty3 · Sep 20, 2006

I know its only for emissions purposes, so that there isnt pressure in the VC. I just dont want oil all over my engine bay, from when it is leaking it doesn't squirt any oil out, so I think I might just be taking that line and bringing it past the tranny, and near ground level to keep any oil off my car

Nice little bit of info on the nitty gritty, of the PCV Tyler.

Dustin

PieEyedPiper · Sep 20, 2006

This thread (only gets more interesting about half way through) has a far more complete description of everything that is going on with PCV mods.
http://www.dsmtuners.com/forums/showthread.php?t=212510&highlight=pcv*

brute · Sep 20, 2006

If your PCV leaks, why not just get a check valve and install it inline after the PCV? That's what I did and it works fine.

MyBeatGSX · Sep 20, 2006

Why not just take it out? Do you have a good reason that's worth keeping it in for?

oldman · Sep 20, 2006

MyBeatGSX said:
I say again, it is for emissions only.

You can say it as many times as you want, still doesn't make it true. Didn't you post a "why is my catch can smoking?" thread. RRE is not a good source for this discussion because both they and Taboo has been pushing vented catch cans for so long that it would be like asking TurboXS if a bleeder type mbc is better than a ball and spring type.

To OP, your original diagram is fine. To make it better, put the pcv back in the VC and add a nice heavy duty check valve where the pcv valve is. The Check valve will stop boost leaking into the catch can/crankcase while the stock pcv will regulate flow when under vacuum, and yes disabling your pcv or venting the breather will change the a/f ratio which anyone with access to the link forum would know. I would also install another inline filter(not fuel filter)/catch can on the breather line and reroute it back to the intake pipe to take advantage of the vacuum when under boost. Hooking up the breather after the turbo will result in boost leaks into your crankcase.

MyBeatGSX · Sep 20, 2006

oldman said:
You can say it as many times as you want, still doesn't make it true. Didn't you post a "why is my catch can smoking?" thread. RRE is not a good source for this discussion because both they and Taboo has been pushing vented catch cans for so long that it would be like asking TurboXS if a bleeder type mbc is better than a ball and spring type.

RRE and Taboo came up with the catch cans to solve a problem, they push them because they know it works. TurboXS is just retarded and stuck on an antique design.

What does that thread have to do with anything? Of course it smokes, that's the blow by gases. The point of my topic was to see if anyone else had as much blow by at idle, which apparently everyone does.

I researched PCV and the history of emissions standards before desiding on the setup I'm running now. I fully understand why its there and what it does. I don't care if you or anyone else wants to go on and on about vacuum in the crank case and ring seal or anything else. These points were beaten to death in the other topic and proved to be false. PCV provides these things when you need it least or not at all (light throttle cruise) and not when you really need it (heavy or WOT accleration). Trust me, I researched why we have PCV in modern cars. The last thing on the engineers' minds was ring seal. If good old Uncle Sam had not stepped in to demand scavanging of crack case vapors, we would not have PCV on cars today.
Its there for emissions only, end of story. You can believe whatever you want, that's your choice. This is no different than trying to convince people that larger exhausts do not decrease torque or that driving like a granny is not the best engine break in method. People have been told inaccurate information or have just assumed things for so long that they will never change their minds.

When I go home this weekend, I'll be sure to get everyone a direct quote about the origins of PCV from the section on emissions in the EFI tuning book I have.

How about you tell us why its not just there for emissions.

Index420 · Sep 20, 2006

http://en.wikipedia.org/wiki/PCV_valve

:thumb:

oldman · Sep 20, 2006

MyBeatGSX said:
How about you tell us why its not just there for emissions.

Like you said, this topic has been beaten to death even in private wiseman forums, nabr...etc. and the majority of the conversation has been focused on how to achieve best crankcase ventilation rather than whether the pcv system is needed. You're absolutely the only one that I see in a consistant bases that is still stuck on the initial questions of "should I vent my pcv?" where as most have moved on to more advance crankcase discussions. The only reason I responded to this thread was because you forced me to with your uncompromising "I'm right, you're wrong and screw everyone elses idea" attitude. Take some steps back from the position you have taken for so long, open your mind, go back and re-read some of our previous discussions as well as other web searched articles that suggests otherwise, information is only good when you choose to listen. BTW, I use to take the same exact position as you and have vented both the pcv and brather valve for years if that means anything.

MyBeatGSX · Sep 20, 2006

From the poorly written boring article said:
Prior to the early 1960s, car gasoline engines ventilated directly to the atmosphere through a simple vent tube of some sort.

....

After some investigation, it became obvious that the road draft tube was allowing considerable amounts of hydrocarbons to enter the atmosphere. The solution was the PCV valve. California was the first US state to mandate installation of a PCV valve around the early 1960s, and the system slowly went nationwide by about 1966.

....

Not all gasoline engines have PCV valves. Engines not subject to emission controls, such as certain off-road engines, retain road draft tubes.

The End.

MyBeatGSX · Sep 20, 2006

oldman said:
You're absolutely the only one that I see in a consistant bases that is still stuck on the initial questions of "should I vent my pcv?" where as most have moved on to more advance crankcase discussions.

This is because that's what these topics keep coming back to. No one is asking about advance ventilation ideas. They all just want to know what's the best catch can setup to run, or is it safe to run without a PCV.

I'm not stuck on my idea and I'm not closed minded. This isn't an opinion I was born with and continue to defend. I developed the opinion after going through many of the discussions, such as you mentioned, on other boards and my own research on the topic. So of course I'm going to defend it.

If you can understand why PCV is used and what it does, it makes the advanced discussions a little more meaningful because you aren't operating from the basis that its deathly nessesary that there be vacuum in the crankcase. No one on here is going to run a vacuum pump system on their street car, so why even get into that? Its not even safe or recommened for a street car.

The bottom line is that for a street car, no pcv and lots of openings for crankcase breathing offers the most benefit (everything I've listed) with the least downsides (not passing visual emissions, morality issues etc).

oldman · Sep 20, 2006

MyBeatGSX said:
The End.

And just like always, you only quote things out of context to support your claim. The above article is great, just as this one.

en.wikipedia.org/wiki/PCV_valve said:
As an engine runs, the crankcase (containing the crankshaft and other parts) begins to collect combustion chamber gases that leak past the pistons. These gases contain compounds harmful to an engine, particularly hydrocarbons, which are just unburned fuel. If allowed to stay too long in the crankcase, or to collect to a too-high concentration, the harmful compounds begin to condense out of the crankcase's air and form sludge on the engine's interior surfaces. Sludge is bad for an engine. It can cause overheating, poor lubrication, and high emissions levels. To keep the crankcase air as clean as possible, some sort of ventilation system must be present.

Prior to the early 1960s, car gasoline engines ventilated directly to the atmosphere through a simple vent tube of some sort. Frequently this consisted of a pipe (the "road draft tube") that extended out from the crankcase down to the bottom of the engine compartment. The bottom of the pipe was open to the atmosphere, and was placed such that when the car was in motion a slight suction would be hopefully obtained, helping to extract combustion gases as they collected in the crankcase. The system was not positive though, as gases could travel both ways, or move not at all, if conditions were just right.

In 1952, Professor A. J. Haagen-Smit, of the California Institute of Technology at Pasadena, revealed that hydrocarbons were a primary constituent of smog, and that automobiles were a major source of those hydrocarbons. After some investigation, it became obvious that the road draft tube was allowing considerable amounts of hydrocarbons to enter the atmosphere. The solution was the PCV valve. California was the first US state to mandate installation of a PCV valve around the early 1960s, and the system slowly went nationwide by about 1966.

The PCV valve is only one part of the PCV system, which is essentially a closed-loop calibrated air leak, whereby the engine is forced to swallow its own combustion gases. Instead of the gases being vented to the atmosphere, gases are fed back into the intake manifold, to re-enter the combustion chamber as part of a fresh charge of air and fuel.

The PCV system consists of: 1) The breather tube , and 2) The PCV valve. The breather tube is just an open tube that connects the crankcase to a clean source of fresh air, such as the air cleaner body. The PCV valve connects the crankcase to the intake manifold from a location more-or-less opposite the breather connection. A typical location is the valve cover, although some engines place the valve in locations far from the valve cover.

Remember that all the air collected by the air cleaner goes through the intake manifold anyway. The PCV system just steals a little of it for its own purposes before giving it back to the intake tract again.

The system relies on the fact that the intake manifold's air pressure is usually lower than crankcase air pressure. The lower pressure of the manifold forces air to flow towards it, pulling air from the breather, through the crankcase (where it dilutes and mixes with combustion gases), through the PCV valve, and into the intake manifold.
Should the intake manifold's pressure be higher that of the crankcase (which can happen under certain conditions), the PCV valve closes to prevent reversal of the exhausted air back into the crankcase again. This is where the positive comes from in the name. Positive is basically a synonym for one-way.

It is critical that the parts of the PCV system be kept clean and open, otherwise air flow will not be correct. A plugged or malfunctioning PCV system will eventually damage an engine. PCV problems are primarily due to neglect or poor maintenance, typically engine oil change intervals that are inadequate for the engine's driving conditions. A poorly-maintained engine's PCV system will eventually become contaminated with oil, causing serious problems. If the engine's lubricating oil is changed with adequate frequency, the PCV system will remain clear practically forever.

Not all gasoline engines have PCV valves. Engines not subject to emission controls, such as certain off-road engines, retain road draft tubes.

MyBeatGSX · Sep 20, 2006

These gases contain compounds harmful to an engine, particularly hydrocarbons, which are just unburned fuel. If allowed to stay too long in the crankcase, or to collect to a too-high concentration, the harmful compounds begin to condense out of the crankcase's air and form sludge on the engine's interior surfaces. Sludge is bad for an engine. It can cause overheating, poor lubrication, and high emissions levels. To keep the crankcase air as clean as possible, some sort of ventilation system must be present.

This does not support your claim to use PCV. It simply says that the gases must be vented. The vent tube works for this purpose.

The bottom of the pipe was open to the atmosphere, and was placed such that when the car was in motion a slight suction would be hopefully obtained, helping to extract combustion gases as they collected in the crankcase. The system was not positive though, as gases could travel both ways, or move not at all, if conditions were just right.

Where does it say this is a problem? Engines ran like this for what, like 50 years? No where in any article does it say anything about PCV being used to increase reliability, decrease wear, increase performance, etc. Its all about emissions. Just show me where an engineer said, "Hey we need some kind of positive ventilation or this engine is gona run like crap/blow up." and I'll completely drop my arguement. It didn't happen like that, it was forced on OEMs by law.

The system relies on the fact that the intake manifold's air pressure is usually lower than crankcase air pressure. The lower pressure of the manifold forces air to flow towards it, pulling air from the breather, through the crankcase (where it dilutes and mixes with combustion gases), through the PCV valve, and into the intake manifold.

And then proceeds to gunk up your intake and combustion chambers.

No_Skillz · Sep 20, 2006

MyBeatGSX said:
Where does it say this is a problem? Engines ran like this for what, like 50 years? No where in any article does it say anything about PCV being used to increase reliability, decrease wear, increase performance, etc. Its all about emissions. Just show me where an engineer said, "Hey we need some kind of positive ventilation or this engine is gona run like crap/blow up." and I'll completely drop my arguement. It didn't happen like that, it was forced on OEMs by law.

Sometimes things are designed for one thing in mind, and the result is that it has positive effects on other components of the system. Smarter people see all posibilities and maximize on their possible good side effects.

MyBeatGSX said:
And then proceeds to gunk up your intake and combustion chambers.

Which is why a simple unvented catchcan will solve the problem. Catchcans are not complex, nor barely even a headache. I don't understand your abhorrence to these little simple devices.

ChiGGz - your diagram looks good. Just add an unvented catchcan (something you will periodically check and empty) in line to the ? in the diagram, then attach to intake.

The Central Hub for DSM Community and Information

So this is the safest way to run PCV? [pics]

ChiGGz

ChiGGz

fourreGsixty3

eldiabloz13

sheldon

fourreGsixty3

MyBeatGSX

ChiGGz

MyBeatGSX

ChiGGz

fourreGsixty3

MyBeatGSX

fourreGsixty3

PieEyedPiper

brute

MyBeatGSX

oldman

MyBeatGSX

Index420

oldman

MyBeatGSX

MyBeatGSX

oldman

MyBeatGSX

No_Skillz

Similar threads

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds