First of all your probably wondering why I even ask.

As some of your know, I have a RevHard manifold and they dont have a spot for the PCV valve in the manifold so what do I do?

Im using the stock like catch can thing in the back of the block but I dont have a hose to go to a PCV valve. Is the point of the valve to SUCK the pressure out of the block rather then let it escape on its own? Why cant I just let it vent out the hole were the hose and pcv valve would go?

Any ideas? Fixes?

 

I searched more and read up on it more on g2ic and it has NOTHING to emissions

Anyhow have suggestions? I know the g2ic.com turbo guide has some ideas but Im not quite understanding how it works and just dont want to do it because "its right" I like to know why Im doing it!

Thanks!

 

This thread is a good read.
Lots of background info
https://honda-tech.com/zerothread?id=697498

 

Yeah I read that thread, AFTER I posted which I shouldnt have done.

Still after reading it im VERY confused like everyone ELSE trying to learn the best PCV setup.

What I dont get is this: I dont care about polluting. I could careless. So why not just use the stock breatherbox connected to the block and let the gas escape on there own. If they are FORCED out how is FORCING/SUCKING (Vacuuming) them out through a small hose going to allow them to exscape fast enough, not to mention they are just recylced back through the intake?

And as for the valve cover; again, why cant you just have a breather filter? Why add these gases?

a 5whp gain on a v8 is going to be this much of a hassle, I dont know why they do it. The gains on a 4cylinder is probably close to nothing BUT if this is whats going to cause my motor to dotonate and BLOW up then im VERY concerned.

Whats a check valve, that what I dont get? I know its the PCV valve in the manifold buy why is it called a "check valve" if there are gases in the crank case why not SUCK or let them be FORCED out ASAP at 100rpms or 10.5krpms?

Im definaltely confused.

 

AFAIK

Yes you can just leave the pcv and valve cover open to atmosphere. They are connected so that all those "harmful gases" can't "pollute" our atmosphere. (But huge diesels and suvs are allowed to pollute more than my little car for some reason)

Having them connected to the intake lowers your octane rating. You do not have to have a vacuum because of the positive crank case pressure.

A check valve lets air go one way but not the other.

 

so why have catch cans and all this nonsense routing?

Just to keep the air we breath clean?

pppiiiiffffff.

Theres got to be more!

 

Vacuum is needed to suck out the blow-by gases because of the PCV valve. The PCV valve only opens with vacuum. If you remove the PCV valve that is inline with the hose and black box then you won't need vacuum anymore.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by devnull &raquo;</TD></TR><TR><TD CLASS="quote">
A check valve lets air go one way but not the other.</TD></TR></TABLE>

No, you have to remove the PCV valve to ventilate the crankcase without vacuum.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RyanCivic2000 &raquo;</TD></TR><TR><TD CLASS="quote">Vacuum is needed to suck out the blow-by gases because of the PCV valve. The PCV valve only opens with vacuum. If you remove the PCV valve that is inline with the hose and black box then you won't need vacuum anymore.</TD></TR></TABLE>
Thanks for clarfying. I used the AFAIK disclaimer

Are you sure it only opens with vaccum? Can you give me a reference source so that I might get a better understanding (helms page#).

But you can vent the breather right since it is just a hole.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RyanCivic2000 &raquo;</TD></TR><TR><TD CLASS="quote">

No, you have to remove the PCV valve to ventilate the crankcase without vacuum.</TD></TR></TABLE>

Why did you quote my definition of a check valve and then post this??

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by devnull &raquo;</TD></TR><TR><TD CLASS="quote">

Why did you quote my definition of a check valve and then post this??</TD></TR></TABLE>

I thought you were referring to the PCV valve. I have a diagram of it somewhere that shows how it works, but I'm at work right now and can't access it.

 

devnull is right here. No need for pcv. The crankase will vent itself. This is how most racing engines are configured. You do not want to "burn" crankase oil vapor. The PCV valve flows to intake manifold.

 

No, you have to remove the PCV valve to ventilate the crankcase without vacuum.


i think that the pcv valve with enough pressure from the crankcase will still open up without vaccum from the intake pulling it open. Its a one way valve, it doesnt matter if its pulled from the intake or pushed from the crankcase.

This is assuming that the stock pcv valve is connected but the hose that goes from the pcv valve to the intake manifold is not connected.

 

your all saying now that you dont need vacuum to allow the pressure to excape... So why not just leave the hole unplugged and let it vent on its own? who knows if this is safe?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by coocoo32 &raquo;</TD></TR><TR><TD CLASS="quote">devnull is right here. No need for pcv. The crankase will vent itself. This is how most racing engines are configured. You do not want to "burn" crankase oil vapor. The PCV valve flows to intake manifold.</TD></TR></TABLE>
it must be how race motors are cause like i said the revhard manifold DOESNT have a spot of the pcv valve. Thats why im kinda stuck in this situation

Again im not worried about emissions or enviroment so if thats the point of a catch can/pcv system then I dont see why just leave the hose that connects to the "breather box" unpluged and let it vent on its own.
Unless....
on g2ic.com they are saying its bad for the crankcase to vent on its own because the reason it vents on its own is because when the piston is coming down its pushing the vapors out and putting stress/wear&tear on the rings. the vacuum is there to suck the vapors out and make the motor work less to exit the vapors on its own

ummm.... maybe i should run a catch can or something.....

xenocron has the simplest idea i can think of to run so far, that would allow vacuum and a catch can to be used. (id run this same setup if its not safe to allow the crank case to vent on its own (without using vacuum in other words))



Decisions Decisions...

 

Wow...

I think I have finally seen the first semi usefull catch can setup on here now...

Full time vacum pressure, nice and clean setup, and will not be affected by boost.

I think I may give that a try...

Now I just have to find some free room in the engine bay to mount my catch can...lol

 

If you really wanted to be trick, you could route both the valve cover breather and the pcv into the catch can.

Good setup, though. Looks like it would work well.

Matt

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jDMJeRk &raquo;</TD></TR><TR><TD CLASS="quote">

Decisions Decisions...</TD></TR></TABLE>

In the diagram above the Turbo is going to be ingesting a tremendous amount of oil vapors and contaminating the intake charge .... not a good idea. Anybody who currently runs an open catch can setup can attest to this because they can visibly see the oil vapors exiting the catch can filter even at idle, just think of the amount of oil vapors the turbo will suck in at WOT!

Realistically speaking the tremendous amount of surface area found within an inter-cooler will trap most of these oil vapors before they contaminate the combustion chamber. You are now left an inter-cooler with a nice oily film making it less efficient as well as contaminating your combustion chamber with oil vapors.

It would be interesting to see how much of these oil vapors gets trapped inside of the compressor housing and inter-cooler over 6 months. Anybody that currently runs this setup care to donate some of your time and inspect the inside of your inter-cooler, take apart your compressor housing, and lower inter-cooler pipes?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jDMJeRk &raquo;</TD></TR><TR><TD CLASS="quote">
on g2ic.com they are saying its bad for the crankcase to vent on its own because the reason it vents on its own is because when the piston is coming down its pushing the vapors out and putting stress/wear&tear on the rings. the vacuum is there to suck the vapors out and make the motor work less to exit the vapors on its own
</TD></TR></TABLE>

Lets use some common sense here and go back to the drawing board.
How Does the stock PCV valve work?

They needed to find a vacuum source which provides a variable vacuum with less draw at idle and more vacuum pressure pulling gasses out at high load (WOT) conditions. The dilemma is that at Idle and low load conditions the vacuum present inside the Intake manifold is the greatest and at WOT the vacuum in the intake manifold is the lowest(almost none). This is the exact opposite of what is needed because their is more blow-by gasses needed to evacuate at WOT (high load) then at Idle!

So they designed a special spring loaded pintle valve(PCV valve) which does the following:

Idle, Low load--- high vacuum pressures fully retract the pintle causing only a small vacuum draw on the crankcase.

Mild load conditions--- vacuum present in the intake manifold is not as strong so the pintle sits in the middle of the pcv valve allowing more vacuum to evacuate the crankcase.

High load + WOT conditions--- their is almost no vacuum present and the pintle is almost completely extended allowing the most amount of gasses to be drawn into the intake manifold.

Engine backfire--- the pintle fully extends and seals to eliminate any gasses from flowing from the intake manifold to the crankcase.


Engine off/backfire --- Low load/Idle --- Medium Load/cruising --- High load/WOT
0 /positive pressure---Highest Vacuum--- SLIGHT Vacuum ---- 0 Vacuum
PCV Valve closed ---- PCV open slightly-- Valve opens more --- Open all the way

//////////////////////////////////////

So on a stock PCV system the PCV valve is open all the way at WOT yet their is NO VACUUM ASSISTING THE CRANKCASE EVACUATION THROUGH THE INTAKE MANIFOLD! Even at a moderate amount of load their is only a little vacuum present which barely helps anything at all.

A forced induction motor has more blow-by than a naturally aspirated engine because the boost pressure inside the combustion chamber causes more blow-by past the rings. If running an open breather setup it would be wise to allow the pressures to be released as freely as possible. Ventilate the crankcase from the 2 plugs on the back of the block instead and open up a second or third port on the valve cover.

Its OK to run an open breather setup as long as the crankcase is adequately ventilated!

Vacuum assistance in evacuating the crankcase would be beneficial from a reliability and a performance standpoint. The 2 best ways to accomplish this now (I'm testing an electric vacuum pump) are through the exhaust(no cat/after cat) or by spending a couple thousand on the mechanical vacuum pump setup through z10 motor-sports.

 

so with a catch can system you wouldnt need vacuum? I mean yeah it wouldnt hurt if you had it but what your saying is just allow the vapors to vent out themselves into a catch can?

 

better yet draw a picture and explain what YOU think is the best vacuum setup with a catch can. I think im going with the catch can idea but what exactly im going to do is unknown

 

Or we could just do what V8 guys have been doing for years...

 

The vapors have no problem venting themselves with a free flowing ventilation system. Here is the best way to do it for an open catchcan setup.




1) remove the breather black box and pcv line and seal the hole with a freeze plug or a piece of aluminum and liquid aluminum epoxy from devcon. If you are using the stock IM than you need to seal the PCV port on th bottom of the IM.

2) Use a 14mm allen (snap-on) to remove the two plugs on the back of the block.

3) Screw in the Honda fitting listed in each port using the washer. Both part#s shown in picture.



4) Run 2 High temp Hoses to the baffled Moroso catchcan. You will need to weld/epoxy in a 2nd port. Place the catchcan in the highest position you can. Mine screws in like stock with 2 10mm bolts here.

5) Optional... drainback the catchcan back to the top of the oil, preferably in the front. Otherwise periodically drain your catchcan manually.

6) Place a filter on the valve cover breather. Better yet, open up a 2nd port in the front of the valve cover with a 2nd filter for increased ventilation.


done

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JalopySiR &raquo;</TD></TR><TR><TD CLASS="quote">Or we could just do what V8 guys have been doing for years...
</TD></TR></TABLE>

Moroso
Crankcase Evacuation System





Old school ..... but works great

 

AWESOME post. That picture is worth a 1000 words.

Thanks for the part numbers

 

balh blah blah... don't feel like reading... but here's my input.

The stock fueling system is designed to work w/ the PCV, which only vents crankcase pressue on idle. When you boost, you make MUCH more crankcase pressure than the stock engine, so the PCV valve is likely to get stuck or spray out some oil. The situation of spraying oil will get worse w/o a PCV valve.... which is why you need to run a catch can. The oil vapor that comes from the PCV is normally reburnt in the engine, BUT it's hot and increases the chances of detonation (stock ecu fuels for this, btw)

When you are turbo, you want to minimize the possiblity of detonation, so you don't want the PCV venting to your intake. On top of that, if you use NO pcv valve, the venting will happen all the time, not just at idle. The stock system vents at idle because it's less likely to cause detonation at idle (burning of the crankcase vapors).

Why shouldn't you just run the crankcase pressure to open atmosphere ? **** the enviroment ?

Crankcase gasses and vapor is toxic to humans. It is also a byproduct of used motor oil, which has been proven to cause cancer. Go pollution.