Finaly got some pics.

[lonerogue]

I second the above, there should be no reason for air to be sucked into the valve cover, forced induction or natural aspiration.

[White95]

I plan on just using a breather to replace the fresh air inlet of my PCV...Is that what your trying to do??

[phoenix64]

The last pic was a quadruple exposure.

I don't know where to get it dynoed, I've heard John Haley is expensive.

As far as the Last right turn before the TB I don't know how else it could have been done. As far as tuning, like the website says, the car runs off the MAF at all times, and it drives and idles better than stock. Hopefully I can get a nice smoth transition once its intercooled.

You guys don't understand how our PCV system works. I had to block off the breather using JBweld, which works awsome BTW, and is easy to sand and shape once its dry.

If you don't belive me go out, block off the breather on your car, take the oil cap off and put your hand there. The first time I started the car after about 5min of idling I heard a whistling sound. I tried to pull the oil cap off with the engine running, but there was so much vacume that I couldn't budge it.

As a side not I noticed a signifigant increase in oil pressure when the engine was hot with the breather. So it is a definit must.

[White95]

The PCV valve when Open will let manifold vacuum suck whatever junk gases that in the crankcase to be sucked into the intake manifold. It needs a soucre of air to help push/pull the crap along. Some people, like me on my 3.4L will put a breather in place of their PCV fresh air tube, other do what this guy did. Its not the engine its self sucking air in, plus if it was blow by cased by the turbo air would be coming out and not in, its the Manifold vacuum which is controled by the PCV letting air be sucked in. Though hot air in you crankcase won't hurt preformance, once the cold air goes through on its way into the PCV system it gets just as hot before getting into the intake.

[mrbako]

i know exactly how the PCV works...i am an experienced automotive technician, and please trust me when i say that i know what i'm talking about. the pcv system allows positive crankcase pressure air INTO the intake manifold to be burned in the combustion process.

i realize the TB hole for the PCV has to be blocked, otherwise you would be pressurizing the crankcase. with that hole blocked now, the crankcase must have another place to vent any positive pressure buildup.

installing a breather filter on a valve cover allows the crankcase to vent to atmosphere now.

the breather should only be relieving crankcase pressure and not acting as a CAI for some magically manifested negative vacuum inside. you have a problem somewhere. it could be a bad valve seal, but i don't know exactly what would cause a vacuum inside the valve cover.

also, like i said before...that positive pressure that gets burned in combustion is very dirty gas. it will certainly have oil in it. running oily air through a small vac line will cause buildup, and eventually cause the line to fail. either by clogging it, or deteriorating it until it falls apart. ideally, you should run a larger line...like the size of a fuel line, to a catch tank w/ a breather on it.

if someone else could explain how the breather is taking in air, i would really like to know. but to my knowledge, i can see no explanation for a valve cover/crankcase to be taking in air.

[mrbako]

Originally posted by White95:
if it was blow by cased by the turbo air would be coming out and not in

if you're feeling air from the filter it is a result of blowby

I plan on just using a breather to replace the fresh air inlet of my PCV...Is that what your trying to do??

there is no "fresh air inlet" on a PCV system. the "inlet" comes from the crankcase, and the "outlet" goes to the intake manifold, just before the throttle body butterfly. it recirculates the vapors from the crankcase into the intake manifold to be burned during combustion, rather than allowing them to escape into the atmosphere.

in a forced induction setup, the outlet from the PCV needs to be blocked to prevent pressurizing the crankcase. this means that the PCV system has been DISABLED. with the system disabled, the crankcase needs to vent somewhere. a brether filter allows the gasses to escape into atmosphere.

the PCV valve is not used during a FI setup on our cars due to the outlet of the PCV being integral w/ our throttle bodies.

[ November 17, 2004, 06:50 PM: Message edited by: mrbako ]

[phoenix64]

No offense but your wrong. Like I said try it block off the hole in your TB and you will see. its an inlet not an outlet.

In the system you describe, there would be no need for a spring loaded PCV valve. All you would need would be a line from the crankcase to the air intake somewhere, so why did GM go to all the trouble of building this elaborate system?

Explain to me how it is that While sitting idling my car built up enough vacume in the crankcase to make it IMPOSSIBLE to remove the oil cap?

Its very easy to test. Walk outside start your car, use you finger to plug the hole in the TB, with in seconds you will feel the vacume.

Please somebody else who has actually worked with one of these step in here and back me up.

[White95]

then would you like to explain to me why I have a fresh air tube going from my Intake elbow to my Passenger side valve cover??? Air needs to come in to replace the air that is being sucked out into the intake system....The whole reason the PCV Valve came into being is b/c the road raft system was to dirty letting the crankcase gases into atmospher. If you have no blow by whats so ever your PCV valve would create a vacuum in your crankcase sucking oil into it. There needs to air circulating in order for the system to be of any good. And as for the breather it acts like a road draft system only it circulates air when the car moving. No air is being sucked into it. It simply acts as a filter passage for air to pick up junk gases in the crankcase and carry them into the intake system.

Also we just went over the PCV system in class a couple of weeks ago. I have a very good under standing how this system works.

[mrbako]

okay...i was wrong...

the hole is a filtered air inlet...i must have misread some other posts from the past on this issue...however...i think there may be a better solution than having that ugly hose and breather combination that you have on your car.

i'm going home right now (from school) to get my spare intake manifolds and TB...my teacher and i have been talking about this for the past 1.5 hours and have a pretty good idea for the breather.

my mistake was thinking that the hole in the tb was the outlet from the pcv valve...it is the fresh air inlet to replace the vapor. with that hole plugged, there would be air going in to the breather, especially in a FI setup with large amounts of air flow. i was thinking that w/ an outlet from a pcv plugged, the pcv was exfectively non-funtional and a simple atmosphereic vent was needed...i was correct, as long as you plug the outlet. plugging the inlet, would not disable the system. it would only force the system to try and get air from some other place to replace the air/vapor that gets sucked into the intake manifold - hence your breather sucking in air.

here is info from a dealer document.
Fresh air from the TB is supplied to the crankcase, mixed w/ blow-by gases, and then passed through a crankcase ventilation valve into the intake manifold. The primary control is through the crankcase ventilation valve which meters the flow at a rate depending on inlet vacuum. To maintain idle quality, the crankcase ventilation valve restricts the flow when inlet vacuum is high. If abnormal operating conditions arise, the system is designed to allow excessive amounts of blow-by gases to back flow through the crankcase vent into the throttle body to be consumed by normal combustion.

[mrbako]

after inspecting the manifolds w/ my instructor, we came up w/ a solution for the breather.

block the passage from the TB to the upper intake manifold by some method. this could be done either by plugging the hole in the TB, cutting a custom gasket, or plugging it in the upper intake manifold.

if you follow this passage through both manifolds, it opens into the drivers side head, near the front of the engine. this is where fresh air enters the crankcase, and begins to mix w/ the vapors. the cycle of the air will carry it down to the lifter galley, then into the passenger side head. The intake manifolds have a large opening near the rear of the engine, from the passenger side head. This is where the vapors come to the PCV valve.

the cycle of the air is important so that the entire engine can be included.

Our plan is to drill and tap the upper intake manifold. without a picture it is hard to describe where, but for now let's just say it's 1 3/4" below the point where the bolt mounting the alternator is (where it kind of points to the intake manifold). inside the manifold here there is an expansion chamber. the alternator is actually in the way of placing the fitting here, so we will drill a little forward of it. we will tap it and install a barbed fitting and attach a vac line to it. we will run this vac line to the intake after the filter, before the turbo.

i will find a picture when i get home to show where i'm talking about.

this method will allow the pcv system to work as normal, cycling air through the entire engine. A breather filter will not be neccesary.

my instructor's opinion is that just installing a breather filter on the oil neck is insufficient. it will only allow for vapors to be cleaned from the passengers side valve cover and head. for maximum efficiency, using the pcv system in a stock manner will allow the engine to be more efficient over time, for a longer time. Oil vapors/exhaust vapors will be forming a sludge in the drivers side valve cover/head if only a single breather is used. you may try installing another breather in your driver's side valve cover. i don't know how well this would work, because inlet for the pcv is in the passengers side head, and it may not pull the air through the entire engine since the passenger's side valve cover is so close and free flowing.

i know someone else here did something similar. they drilled a few holes in the throttle body pcv passage after they plugged the hole. this would accomplish the same thing, except it would not be using filtered air.

[Tyler]

i think it will be a lot less of a hassle to just use a breather.. lol

[phoenix64]

MrBako has a good point that sucking in air to only one side of the engine is a poor solution at best. My oil's operating temp went up enough to decrease oil pressure at idle by about 10psi. If you come up with a solution to this that could be effectivly implemented I would be very interested.