crank case evacuation setup?

[yenkoz28]

I have a D1SC setup on a 91 Z28 and in the procharger instructions they say to route the PCV tubing down by the frame. With this setup it is just venting to atmosphere. Has anyone set it up to route the PCV into the intake tube for the procharger? Do some of the procharger kits do this already?

[WA2FAST]

I have seen different blower kits run the PCV lines to end up either in front of the air filter (pretty much as close as you can get it), or directly into the intake tube on the blower. The modular kits go into the intake tube.

[SnakeIs]

With it in the intake of the blower, doesn't the blower pull enough vacumn to "suck" oil out of the crank case? That has always worried me, thats why I havent done it.

[WA2FAST]

I would suggest doing whatever ATI says... I know that I am going to do a modified version of what they say to eliminate a clutter of tubing, but essentialy the same thing. In my case, I just wish I knew weather the positive airflow comes from the valve cover or the pcv spot. That is what I don't know.

[yenkoz28]

The positive pressure is coming from the crankcase which vents to the valvecover. The pcv is just a checkvalve that prevents backflow into the valvetrain. My only question is does ATI run the pcv into the supercharger intake tube on some of the kits? And the reason I ask this is, because I wonder about hydrocarbon buildup on the impeller over time. If they run it on some of the kits then it must not be a problem. I just don't like the idea of running the pcv to atmosphere and not pulling a vacume on it. Over time you could run into gasket sealing problems and the rings won't seat as well nor will the oil stay as clean.

[StangQuest]

I was having some crankcase pressure issues when I first put my P600b on. I had my PVC in its' stock location on the intake and I put a breather on the valve cover. The problem was whenever I was under boost the PVC closed and all the crackcase pressure would vent out of the VC breather and bring with it a decent amount of oil which would end up all over my headers. I then tried putting the PVC line on the inlet of the blower with little success.......the VC breather was still blowing oil all over the place. Although, I think the reason that didn't work was because I'm a knucklehead and put the PVC line directly above where the surge valve feeds into the blower. With the engine running I could pull the PVC line out of the blower inlet and feel blowing air.

Presently I have the PVC back in it's stock location on the intake and a spouted breather with a vacuum line running to the blower inlet. I guess my logic is, once I'm WOT under boost the PVC will close and there should be sufficient vacuum from the blower inlet, since my surge valve should be closed, to pull the pressure from the crackcase. So far so good although I have had to push the PVC back down into it's location a couple of times.

Just my 2 cents.

[WA2FAST]

ATI on my setup says to run a tube from the valve cover nipple to a T. This T has one line from the valve cover (that I was talking about), the PCV, and then the other one is open. I am trying to figure out what would be wrong with throwing a breather on the valve cover, plugging that nipple on the oil fill stem (trying to eliminate clutter from extra tubes... I do NOT want to put a tube from the cover to the PCV if at all possible), and just venting the PCV... but then at the same time, I don't think the PCV would even work without vacume attached... I am so confused as to what to do.

[paluka21]

Originally posted by WA2FAST
ATI on my setup says to run a tube from the valve cover nipple to a T. This T has one line from the valve cover (that I was talking about), the PCV, and then the other one is open. I am trying to figure out what would be wrong with throwing a breather on the valve cover, plugging that nipple on the oil fill stem (trying to eliminate clutter from extra tubes... I do NOT want to put a tube from the cover to the PCV if at all possible), and just venting the PCV... but then at the same time, I don't think the PCV would even work without vacume attached... I am so confused as to what to do.

Don,
I am in the same shoes as you! I have a breather on the valve cover, I have a vacuum hose running from the fitting on the valve cover to a T above the PCV. the T comes from the valve cover, then to the pcv, then the other side is vented freely instead of going back into the upper intake manifold. I have the fitting on the back of the upper plugged.
I am getting oil pushed from the valve cover onto my headers as well and onto the intercooler piping. This cannot be good, and ATI told me this is the best way to vent this, however I find that hard to believe.
Looking for solutions! I don't see where a check valve would help in this situation, as there really would be no place to put it, since the Pcv is venting to atomosphere on the other side of the T anyway.

DAN

[WA2FAST]

Well, the whole idea behind the check valve is to run it inline to the PCV to not allow any air to travel into the PCV under boost... only when your motor is making vacume... makes sense to me, just that you would need to plug the line that leads from the t-body to the valve cover on both ends. The only problem with this is that you are letting un-metered air into the system. It is so damn hard to figure this all out. I really, REALLY would like to see how supercharged applications from the factory (lightening, cobra, focus) have the pcv setup.

I mean... it's just tempting to put a breather on the valve cover, plug the nipple on the valve cover, and just leave the pcv either open, or just take the damn thing out and let it be... just worried that oil will end up everywhere. So then in that case, what if you gutted out a PCV and put it back in (so that it would fit in the gromet nicely) and vented the now open PCV to a catch can or something? Then I would tend to beleive that you wouldn't have as many issues with all of the crank case venilation going through the valve cover. PCV's are bassicaly check valves anyway... just not for positive pressure... they close when there is no vacume present, just that they won't hold boost out, that's why you need either a special PCV or a check valve.

I don't know... I am at a loss... I want to eliminate clutter and lines under the hood everywhere, so I do NOT want to hook it up the way that they say... I am at a loss though... what do other people have?

[paluka21]

Originally posted by WA2FAST
Well, the whole idea behind the check valve is to run it inline to the PCV to not allow any air to travel into the PCV under boost... only when your motor is making vacume... makes sense to me, just that you would need to plug the line that leads from the t-body to the valve cover on both ends. The only problem with this is that you are letting un-metered air into the system. It is so damn hard to figure this all out. I really, REALLY would like to see how supercharged applications from the factory (lightening, cobra, focus) have the pcv setup.

I mean... it's just tempting to put a breather on the valve cover, plug the nipple on the valve cover, and just leave the pcv either open, or just take the damn thing out and let it be... just worried that oil will end up everywhere. So then in that case, what if you gutted out a PCV and put it back in (so that it would fit in the gromet nicely) and vented the now open PCV to a catch can or something? Then I would tend to beleive that you wouldn't have as many issues with all of the crank case venilation going through the valve cover. PCV's are bassicaly check valves anyway... just not for positive pressure... they close when there is no vacume present, just that they won't hold boost out, that's why you need either a special PCV or a check valve.

I don't know... I am at a loss... I want to eliminate clutter and lines under the hood everywhere, so I do NOT want to hook it up the way that they say... I am at a loss though... what do other people have?

I may try to talk with Larocca about this to see what he says. Either that or a few of the guys at Kauffmans as this is where I may end up getting the car tuned since Laroccas is about a 5 hour drive for me.

DAN

[WA2FAST]

I would call Walsh, but he is impossible to get ahold of and I really don't feel like bugging him about something simple and small like that... at least not till I was ready to make an appointment to have it tuned.

[9ivgtvert]

I had mine running right after the throttle body but this was on a holley systemax intake. The only problem was oil was coming up through the tube and draining down the throttle body, down the mass air and down the intercooling pipe. Not alot but I just had the motor rebuilt and thought the rings might not have sealed right. So I was told to just plug the hose going to the pcv and cap the hole I had going into at the intake. No more oil and no problems and the pvc doesn't pop out. It is normal for oil to come out a breather cap especially at wot. Thats what happens when you take that hose off that use to run back up to the intake. The oil just got sucked up from the intake. Now without the hose it just blows out the breather.

[SnakeIs]

The above post is exactly what I was told also. Thats why the factory had the line to the TB off the valve cover so when you ran the car hard the oil that made its way up just got sucked into the intake and burned.

Here is what I have done and I have minimal oil that comes out of my valve cover breather now. I am using the PCV from the Turbo SVO mustangs which is designed to seal under boost and I have the PCV line to the intake in the stock location. I have vacumn cap on the valve cover nipple and K&N breather in place of the oil cap. I only notice a little bit of oil droplets on the TB that comes out of the breather when I really run the car hard. It has worked so far for me. For you guys that have the problem with the PCV popping out, go to the parts store and buy a new rubber grommet for the PCV, that solved my problem totally and mine was really hard and cracked when I removed it.

[WA2FAST]

I was thinking about just venting the PCV to atmosphere, capping the intake vacume spout, capping the t-body spout and the valve cover spout and throwing a breather on it. Sound good?

I also thought of leaving the PCV where it is, getting a new gromet (SnakeIS... you read my mind, I have heard of that too) putting in a boost sensative PCV, and also for good measure, putting a check valve in that PCV line as well.


Which sounds better?

[SnakeIs]

I think that'll solve your problems, I just wish I could figure out where to get the check valves, I want to install one too just for safety... I can find small ones at the aquarium stores but none of them will fit that big damn PCV hose...