I didn't say standing. I said PUMP the brakes. Everytime you pump the brake pedal, another quantity of un-metered air is being introduced into the engine and the wideband will show it. Go try !


Thats what my post says so far

1. It is tiny on your car, not all cars and trucks, some use vacuum systems or other means of providing PCV action which increase flow dramatically.
2. It is random because there will always be a differential present, and that differential of pressure will generally be at the whim of individual cylinder intake valve pull events and overall engine pressure ratio and resembles wave-like properties, thus you never know what you are "getting" when using intake-driven PCV from one moment to the next. If your car has a 'negligible total amount of flow' due to a restrictive PCV valve or lines/system, that is not ALL cars and it is still random on a small, insignificant scale.

There is no compensating for insignificant pcv source. You just said its a tiny percentage and now you want to compensate for it in the tune? There is no compensating because it acts like part of the throttle body bypass flow total. Its part of the regular operating idle airflow total % Just like with a carburetor. It does not need "compensating for" specifically, like an extra job on the table.

that was my original point to begin with, please check my first post in the thread. I am saying the car has a source for engine pressure release there at the metered air post maf source.


/yawn
By the way,
The correct way to actually answer my original question is that the check valve on the valvecover is closer to the higher point in air pressure differential on an engine running WOT in a N/A application, and is therefore more likely to hold the pressure in the crankcase lower due to it's location than the OEM filtered post maf source will. I guess I know all along too.

 

I really hope you aren't actually tuning cars for people like you claim.

 

The PCV system is closed loop, which will allow oil vapors into the intake even from the "clean line". You can run a dual catch can system or vent like this and use a single catch can on the dirty line. This helps eliminate that by venting those vapors out and not letting unmetered air into the engine. Especially in road race style of driving with lots of engine braking this helps a ton with keeping the intake clean of oil.

 

Well sort of. The cap breather doesn't catch anything, it wont help anything stay clear of oil, in fact it might even let oil out and spray into the bay. Its not a catch can. Its just a check valve right?

Unmetered air is the least of my concern, forget I even mentioned it.
Vapors out, I understand. Thats a good use for the breather cap, like I mention above. If you draw a picture of an engine at WOT, then draw a picture of the PCV system, complete all the way to maf... Now, fill in the pressure scalar units each. Write them into the picture, where do you think/feel the pressure will look like at each point?

Would you like a picture to describe what I am trying to paint?

Really hope your done being a dick to anyone whos intelligence you feel threatened by.
http://s9.photobucket.com/user/kingt...v9iza.mp4.html









http://s9.photobucket.com/user/kingt...7m3ni.mp4.html

I have all kinds of car related fun, welding, wiring, ECU assembly/tuning, trans builds, whatever wherever life takes me.

 

To answer your question/comment yes I believe the GM cap is a one way check valve pressure release. Yes ive seen a slight amount of oil mist on that side of the engine (not noticeable unless you are looking for it). On a high mileage engine it may be worse.

 

Who said anything about catching anything?
It does in FACT help keep oil out of the intake, ask me how I know...
Instead of the oil vapors traveling up the clean line into the intake under engine braking the pressure is released through the breather. (I also have a 1-way check valve in the clean line).
The filter on the breather will stop any oil from actually coming out, but can get a little soaked in it.

Why are you only talking about WOT? That is the least of my concerns.

 

1. During engine braking and cruising the check valve is open for the intake manifold to provide PCV suction. There is nothing headed towards the air filter tract (clean line?) as fresh air is being sourced from this location to feed the crank case as the intake manifold removes air from the crank case

2. You should not have check valves on all PCV lines because during intake manifold vacuum the crankcase pressure will go south and pull on the engine oil seals (causing a busted oil seal, rear main, front main, oil pan, etc) This is why the open "clean line" exists. I assume the clean line is the air filter tract, as your terminology is lacking (you say intake but there are two intakes on the car, which one are you referring to? The manifold or air filter intake? )

 

Here's what I know. Crankcase pressure is bad. Crankcase vacuum is good. Maybe not in every singe instance but that's how I see it. I pull 14" of vacuum on my crankcase & my engine loves it.

 

If you're going to claim high intelligence, make sure you use the correct form of your/you're and spell "whose" correctly. You're over-compensating if you think you're threatening to anyone here.

Seriously, the PCV system for the LS platform and the common methods of fixing its shortcomings are not rocket science here. That valve cover breather combined with a vented or non-vented catch can works perfectly. Tuning for it is a non-issue. Anything else being said is just verbal diarrhea.

 

1. Internet spelling rules means k, ur, ther, lol/rofl type words all fly. I am not an engrlish profeszor and I misspeell all the tiem even when I am. If you are looking for spelling correctnesh, a cars forum is not a great locashun. But I do appreciate the looking out, yeah whos and whose is lose on me atm.




2. Ah but it IS rocket science. Everything is rocket science. Even if just because I make it that. When I cook, clean, or modify my car, its always science.

 

All of this talk is a out unmetered air... Again, my breather will not allow air to enter the motor with the check valve... Just saying

 

Understood by 99% of the people here.

 

If you remove the line from VC to intake it doesn't really matter either way. Free air in the crankcase doesnt effect anything.

 

Yes, true but not all breathers are designed this way. I can think of one thats very popular that is just a filter on top of hollowed out oil cap.

Sorry brother but you're dead wrong. The stock pcv system pulls air from the TB, which is after the maf and the computer can see and account for this. As soon as you open it to atmosphere the computer can no longer see how much and when the air is getting ingested, remember after it goes through the engine its pulled into the intake neck and sent in for combustion. Opening to atmosphere introduces extra air just like an intake leak. Your o2s should catch it to a certain degree but that only works so much when the maf and 02s dont jive. A check valve makes this a non issue but again not all breathers have this.