Have you ever had your blower off and noticed that there is oil in your manifold? Or had your intake tube off and seen oil in the intake tract and throttle body? I think I may have found something to help with that.
The problem seems to be with the Positive Crankcase Ventilation system. Below is a diagram of how that system works. Air comes in the intake, into the passenger valve cover, through the crank case, out of the driver side valve cover, and into the back of the blower to be burnt. IN MY OPINION, the intake tract/ back of the blower route, provides the best means of ventilation for the crank case, so simply venting both sides isnt viable. Some guys like to run a breather on the passenger side, if you look at the drawing, you can see that this would end up with unmetered air entering the back of the blower. Thats not good. Like I said, it is my opinion, that the factory path be retained.
http://img857.imageshack.us/i/pcv.gif/
Lets talk about the effects of puddling oil. It gums up the rotors and intercooler, and effectively reduces the octane of fuel. This leads to lost power and detonation.
The logical solution is to run a catch can between the blower and drivers side valve cover. That will solve some of the problem. Not all of it. Remember the oil in the intake tract and throttle body? There is something else going on. Others have mentioned this before.
The problem is the check valve on the drivers side valve cover. They are suppose to only flow one way. They are crap though. Go pull yours off, and try to blow through it both ways. You shouldnt be able to, you probably can though. When that check valve fails and you go into boost, you reverse the flow of the PCV system and the oily air ends up flowing out of the passenger side valve cover and into the intake tract. Once the oil hits the intake tract, and whatever else, it puddles.
Now that we understand the problem, we can solve it. Part of the solution is to use a catch can. The other part of the solution is to use a quality check valve. This is where my journey began...WEEKS AGO.
A few guys are running an Andair Check Valve. ANDAIR CHECK VALVE from Aircraft SpruceThis is a quality piece. The important part of this check valve is the opening or "cracking" pressure. The Andair, opens at less than 1psi (2 in hg, vacuum) and will block up to 50psi. Look at the price though. 67$ + tax.
I knew there was a better solution. I have found some check valves with a 1psi cracking pressure, 1/4" NPT male fittings (like the Andair valve), and capable of blocking well over 300psi. These numbers are from the manufacturer. They have told me that this check valve is P E R F E C T for this application. Price? $25 + shipping. Who wants one?
The problem seems to be with the Positive Crankcase Ventilation system. Below is a diagram of how that system works. Air comes in the intake, into the passenger valve cover, through the crank case, out of the driver side valve cover, and into the back of the blower to be burnt. IN MY OPINION, the intake tract/ back of the blower route, provides the best means of ventilation for the crank case, so simply venting both sides isnt viable. Some guys like to run a breather on the passenger side, if you look at the drawing, you can see that this would end up with unmetered air entering the back of the blower. Thats not good. Like I said, it is my opinion, that the factory path be retained.
http://img857.imageshack.us/i/pcv.gif/
Lets talk about the effects of puddling oil. It gums up the rotors and intercooler, and effectively reduces the octane of fuel. This leads to lost power and detonation.
The logical solution is to run a catch can between the blower and drivers side valve cover. That will solve some of the problem. Not all of it. Remember the oil in the intake tract and throttle body? There is something else going on. Others have mentioned this before.
The problem is the check valve on the drivers side valve cover. They are suppose to only flow one way. They are crap though. Go pull yours off, and try to blow through it both ways. You shouldnt be able to, you probably can though. When that check valve fails and you go into boost, you reverse the flow of the PCV system and the oily air ends up flowing out of the passenger side valve cover and into the intake tract. Once the oil hits the intake tract, and whatever else, it puddles.
Now that we understand the problem, we can solve it. Part of the solution is to use a catch can. The other part of the solution is to use a quality check valve. This is where my journey began...WEEKS AGO.
A few guys are running an Andair Check Valve. ANDAIR CHECK VALVE from Aircraft SpruceThis is a quality piece. The important part of this check valve is the opening or "cracking" pressure. The Andair, opens at less than 1psi (2 in hg, vacuum) and will block up to 50psi. Look at the price though. 67$ + tax.
I knew there was a better solution. I have found some check valves with a 1psi cracking pressure, 1/4" NPT male fittings (like the Andair valve), and capable of blocking well over 300psi. These numbers are from the manufacturer. They have told me that this check valve is P E R F E C T for this application. Price? $25 + shipping. Who wants one?
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