PCV / emissions plumbing ?

[Sick Puppy]

I originally posted this question on TF but wanted to get some more input.
This is for my PE, large VAM, FMIC install project.
It's on my GT Turbo (SVO wanna-be) convertible. ;)
I keep adding SVO parts as upgrades, does that count?...lol

http://forum.turboford.org/ubb/ultimatebb.php?ubb=get_topic;f=2;t=058372

TIA!
Paul

[blueboss]

http://www.svocop.com/forum/showthread.php?643-Air-Oil-Separator

Post #3 is my setup. Sorry about the pics....
I'm not sure if this is what you're looking for but maybe it'll help get you to where you want to be???
This will work with either FMIC or standard.

[Sick Puppy]

Thanks for the reply and links, lots of good info and ideas.
One of the guys on TF told me two of the lines I questioned (red & yellow) are for the cruise control so I need to keep those.
I'm pretty sure the 90* elbow I have for the compressor outlet has a boss I could drill and tap for that fitting.
I'll try leaving the breather line (blue) as is to start, my setup is going to stay fairly conservative at ~18psi. If I find I'm having oil control issues I can use the info given and do a catch can setup.
Paul

[blueboss]

When reading this description, remember this as it is relevant to this discussion. There is no such thing as a vacuum. What is widely considered a "vacuum" by most everyone is actually an area of low pressure. Air ALWAYS moves FROM an area of high pressure TO an area of low pressure. It's pushed, not pulled. Think of how an air compressor works.....moving on. From what I can see from your pic on TF, the blue hose/line is the "high speed/low vacuum" part of the pcv system. A user on TF described that accurately. The description offered by the user "B" should be taken with a caveat. He states "The air moving through the red arrow line is supposed to be able to pull some vacuum on the yellow arrow line. This is supposed to allow the cruise control to operate with some boost pressure, since it operates with vacuum."

The only way this will work as he describes is if the fitting on the charge tube that the yellow and red lines are connected to is a check valve. The charge tube sees manifold vacuum, atmospheric pressure, and boost pressure. If that fitting on the charge tube IS a check valve, when the charge tube is pressurized, the valve closes, blocking the boost pressure from reaching the red and yellow lines and leaving them "connected" to each other and to the low pressure area at the turbo inlet via the red line and everything works as he described. Here's the caveat, if that fitting on the charge tube IS NOT a check valve and simply an open fitting, when the charge tube is pressurized, both the red and yellow tubes see boost pressure with some of it bleeding off back into the turbo inlet via the red line. That creates a "bypass loop" which lowers your overall boost entering the engine. I would bet the factory didn't design it that way as I can see the boost reference port on the impeller housing that normally goes to a boost controller. Under the same conditions, the check valve on the yellow line would simply close, restricting any air movement. My guess is that fitting on the charge tube *should* be a check valve of some design. The reason I mentioned the whole "no vacuum" thing at the onset of this is because with this last scenario, under boost, that fitting and BOTH tubes see boost pressure. There will be no draft tube effect on the yellow port

One reason your cruise control *may not* be working is the check valve on the charge tube and/or on the yellow line may be bad/blown/non-existent. This allowed boost pressure to reach the cruise control diaphragm and rupture it. But to keep your cruise control with a fmic and the setup you have, I'd guess you'd need to find a way to reference vacuum while under boost.

Sorry for the long, drawn out explanation.....I was bored.

[Sick Puppy]

Sorry for the long, drawn out explanation.....I was bored.

bb, thanks for the great explaination, that really helped me understand what all that tubing was for.
I hope you're 'bored' next time I have a question like that. ;)
Paul

[Under Pressure]

All these years I would tell my lead I was looking for a vacuum leak and at the parts store I would ask fr a vacuum hose instead of a low pressure hose. Its like the weather, we have a low pressure moving in.

[blueboss]

It's all semantics. If we're ever talking over a few beers, I'll blow your mind with electron vs. conventional theory. Basically, electrons flow from negative to positive, not the other way around.....yeah, I need help.....