Oil separator
Racer
Joined: Nov 2003
Posts: 451
Likes: 1
From: Ringgold Ga.
I have a Cambell Hausfeild seperator on the line going to the air filter and one on the line going to the intake. The one going to the air filter doesn't catch much oil, but the one going to the intake gets about a tbsp every 1000 miles. I don't have a catch valve. Never had any knock running 10#'s with a D1 on a stock motor.
St. Jude Partner since 89
Joined: Oct 2005
Posts: 774
Likes: 4
From: Lebanon, TN
St. Jude Donor '09
Originally Posted by AVB
I forget if that connection on the throttle body is before or after the throttle blade. If after the throttle blade it's pulling vacuum and therefore the answer is yes. It would pull vapors. If not, it's a source of air to replace what the pcv is pulling shouldn't be an issue at least when there's not alot of airflow. During high-airflow, however the throttlebody is sucking air and that connection is then seeing some vacuum. If it were me it would have a separator as well.
It's before the blade and I already knew which way the vacuum was going I was really just asking if it could reverse flow. If you pull the hose and put your finger over it, you can tell that the vacuum is coming from the hose side (valve cover) and not the throttle body side.
Do you think that vaccuum that you're saying is getting created at high air flow (rpm) could overtake the vacuum from the other end of the equation (at the manifold) at that same high rpm thus causing a reverse flow? That's my real question...
Safety Car
Joined: Apr 2004
Posts: 3,932
Likes: 8
From: Hayward California
Originally Posted by Nithros
It's before the blade and I already knew which way the vacuum was going I was really just asking if it could reverse flow. If you pull the hose and put your finger over it, you can tell that the vacuum is coming from the hose side (valve cover) and not the throttle body side.
Do you think that vaccuum that you're saying is getting created at high air flow (rpm) could overtake the vacuum from the other end of the equation (at the manifold) at that same high rpm thus causing a reverse flow? That's my real question...
Do you think that vaccuum that you're saying is getting created at high air flow (rpm) could overtake the vacuum from the other end of the equation (at the manifold) at that same high rpm thus causing a reverse flow? That's my real question...
Arnel
St. Jude Partner since 89
Joined: Oct 2005
Posts: 774
Likes: 4
From: Lebanon, TN
St. Jude Donor '09
I see what you mean about that (even though, on my car, I haven't seen any oil in the throttle body but I know some is getting past my catch can and going into the manifold).
Thread Starter
Pro
Joined: May 2005
Posts: 710
Likes: 0
From: Northfield Center Ohio
Originally Posted by Nithros
I see what you mean about that (even though, on my car, I haven't seen any oil in the throttle body but I know some is getting past my catch can and going into the manifold).
St. Jude Partner since 89
Joined: Oct 2005
Posts: 774
Likes: 4
From: Lebanon, TN
St. Jude Donor '09
Originally Posted by SCannon
Time for a Dual Setup?
I have mine mounted on the head but I've read where it's better to mount them further away from the heat like to the frame at the front passenger side corner (under the hood).
Le Mans Master
Joined: Oct 2005
Posts: 7,088
Likes: 1,829
From: Metro Detroit Michigan
Originally Posted by AMERICAN_HP
The use of a check valve is absolutely necessary on a PCV system when going with F/I. Although a pcv valve does block air movement when you "Blow" through the valve, it does not work properly when applying large amounts of boost. The average person blows about 1.5-2 psi. Throw 7-14 psi at it and its a whole different ball game.
The PCV valve will fail.....The PCV valve was not designed to withstand back pressure, it was designed to allow unobstructed flow OUT of the CC.
The PCV valve will fail.....The PCV valve was not designed to withstand back pressure, it was designed to allow unobstructed flow OUT of the CC.
We had one guy who could blow 3 psi!
Still not sure about needing a check valve in addition to the PCV valve.
Not a lot of time on my setup (only 2000 miles), but so far the PCV valve is preventing backflow and holding up fine with 10 lbs boost, and a lot of time spent under boost.
Le Mans Master
Joined: Oct 2005
Posts: 7,088
Likes: 1,829
From: Metro Detroit Michigan
To answer the question about backflow into the throttle body:
At full throttle, there is almost no vacuum in the manifold where the PCV valve connects, and almost no pressure differential between that and the air supply connected to the throttle body, so blowby could enter the engine through both hoses.
On a FI application, the PCV is closed under boost, so all the blowby must exit somewhere else. Can't keep the supply side connected to the throttle body, or you'll pressurize the crankcase. On mine, the hose that normally goes to the throttle body is connected to the air filter, and that's where all the blowby goes.
So far, this hose is dry inside, but I think concerns about condensing fuel vapors etc. in the intercooler have merit. Best to keep the cooler clean, I would think.
Best thing might be the the oil filler breather a lot of guys have. Filtered air enters under vaccum, and blowby vents under zero vacuum or boost. The throttle body and air filter connection are eliminated, so there's no chance of oil mist or other vapors getting in.
I'll be putting on RoadRebel's custom high-tech super-secret oil filler breather next time I see him.
At full throttle, there is almost no vacuum in the manifold where the PCV valve connects, and almost no pressure differential between that and the air supply connected to the throttle body, so blowby could enter the engine through both hoses.
On a FI application, the PCV is closed under boost, so all the blowby must exit somewhere else. Can't keep the supply side connected to the throttle body, or you'll pressurize the crankcase. On mine, the hose that normally goes to the throttle body is connected to the air filter, and that's where all the blowby goes.
So far, this hose is dry inside, but I think concerns about condensing fuel vapors etc. in the intercooler have merit. Best to keep the cooler clean, I would think.
Best thing might be the the oil filler breather a lot of guys have. Filtered air enters under vaccum, and blowby vents under zero vacuum or boost. The throttle body and air filter connection are eliminated, so there's no chance of oil mist or other vapors getting in.
I'll be putting on RoadRebel's custom high-tech super-secret oil filler breather next time I see him.
Last edited by Warp Factor; Apr 11, 2006 at 08:42 AM.
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Le Mans Master
Joined: Oct 2005
Posts: 7,088
Likes: 1,829
From: Metro Detroit Michigan
Originally Posted by Nithros
Good information. I've read a lot of your posts and everytime the jet boat pops up there seems to be a lot of knowledge/experience there. Thanks!
But dang it, it's not a jet boat!
It's a V-drive.
St. Jude Partner since 89
Joined: Oct 2005
Posts: 774
Likes: 4
From: Lebanon, TN
St. Jude Donor '09
Originally Posted by Warp Factor
Thanks.
But dang it, it's not a jet boat!
It's a V-drive.
But dang it, it's not a jet boat!
It's a V-drive.
Thread Starter
Pro
Joined: May 2005
Posts: 710
Likes: 0
From: Northfield Center Ohio
Originally Posted by Nithros
It's time for something... For now, I put a clear filter in there to gauge the problem.
I have mine mounted on the head but I've read where it's better to mount them further away from the heat like to the frame at the front passenger side corner (under the hood).
I have mine mounted on the head but I've read where it's better to mount them further away from the heat like to the frame at the front passenger side corner (under the hood).
