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Discussion Starter #1
Any of you guys have a catch can installed. How did you plumb it pics would help out alot. Thanks guys
 

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Where u take te old line out is where the new go in. One is just left bottom kin of hidden bottom left of throttle body and te other is back right of the manifold


Sent from my iPhone using AutoGuide.com App
 

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There are s few good threads on the subject, with pics!
 

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We need info on how to plumb it for a V6. The routing is not the same as the V8. I would like to add one too.
 

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When totally stock 5 fits directly onto 4.
ALL you disconnect is the stock Y hose at position 5 from the PCV orifice at position 4.

You then run New Hose 1 from 4 to the new catch can.
From the new catch can you run New Hose 2 to position 5.....entry point into the stock Y hose.

 

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here is my install (V6)
Totally wrong.
You've connected the catch can into the fresh air supply line which supplies fresh air from the intake tube to the rear left valve cover. You'll only catch a little oil during flow reversion (opposite to normal) with your set-up.

The PCV is on the rear right valve cover on the V6...Majority of oily air comes from the PCV to the intake Y hose as I showed above.
 

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The PCV orifice is always on the stale oily air line which runs to the intake manifold. The PCV orifice is on the right hand valve cover on V6. (stale oily air side shown in red).

The PCV fitting on the left valve cover has no orifice (restrictor) and connects to the fresh air supply line running to the air intake tube in front of the throttle body. (shown in green).



Flow direction is shown with arrows.


GM Service Manual Description of Pontiac G8 V6 PCV System.
 

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Discussion Starter #14
Now I'm confused lol should we have two catch cans if he's getting oil from the fresh air line?
 

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Now I'm confused lol should we have two catch cans if he's getting oil from the fresh air line?

Dont be, This way or that we need only one catchcan (N/A). Its just little discussion on where/how to install it. :)



So HSV-GTS ...I think I am following with you more now, and I went read in an old thread of mine (for another car setup which I was deep in it back then),

first off, I got mixed in "left" and "right", excuse me for that, I always do in cars. it's good that I used at some point "driver side" expression, it made me rethink the whole thing.

So mate, per your argument, the green line is the breather line to crankcase, entering at "US driver" side cover, and the PCV on "US Psngr side" goes to manifold. That could be, (then I must have mexed where the joint goes, I'll check em tomorrow morning if weather helps :)
BUT how come the catch can I mounted on the green line traps things?
 

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So mate, per your argument, the green line is the breather line to crankcase, entering at "US driver" side cover, and the PCV on "US Psngr side" goes to manifold. That could be, (then I must have mexed where the joint goes, I'll check em tomorrow morning if weather helps :)
On the G8 V6 the Fresh Air Supply Line (green) runs from the intake tube in front of the throttle blade to the crankcase, entry point to crankcase is on USA drivers side valve cover at the rear.
On the G8 V6 the stale oily air (red) comes out of the rear of the USA passenger side valve cover where the PCV orifice (restrictor) is located.


On the G8 V8 the Fresh Air Supply line (green) runs to the USA passengers side valve cover at the front.
On the G8 V8 the stale oily air (red) comes out of the rear of the USA drivers side valve cover where the PCV orifice (restrictor) is located.
Stale oily air always runs to the intake manifold.



BUT how come the catch can I mounted on the green line traps things?
Read the GM Service Manual description above. During abnormal conditions there will be "backflow".
I'd imagine coming hard off the throttle could be one "abnormal condition" where you'd have more pressure inside the crankcase than in the air intake tube in front of the closed throttle blade. You're trapping things with your current install only when there's a backflow or reversion of the normal fresh air flow direction.
Disconnect both your current lines from your catchcan and have someone rev the engine up and down while you hold a finger over the end of both your lines, you'll soon tell from slight suction or slight pressure on your finger which way the air flow is during various conditions.
 

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Sick and trapped in bed, I get more time to browse , here I'm back in again :)

On Camaro V6 forums a good thread was going on the argument about on which side to put the catchcan. Majority agrees the configration HSV-GTS have put above being correct from "US pasngr side cover to intake manifold (myself starting to agree to some extent). But interestingly with other people like myself who had put it on the "clean side" (US driver cover to intake pipe) and still having oil/mixture being trapped in the can! (reasoned that at WOT reverse flow occures on the clean side).

Eventually ended in "do we need 2 cans"?!

HSV-GTS-300 (Paul I guess, from the Commo origin land!).. sound well informed on this, and I like to hear from you ...

So ...
- Is it better to trap regular blow-by before it gets back into intake manifold (OE has planned it that way).
- Or better to trap possibly "reversed flow blow-by" at WOT from getting to TB (which would influence TB performance on long term for sure)
- Or slam another can :)


Don't I love forums! ... especially If I find I could be wrong and corrected :)

Edit: you've just posted above, thanks HSV
 

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So ...
- Is it better to trap regular blow-by before it gets back into intake manifold (OE has planned it that way).
- Or better to trap possibly "reversed flow blow-by" at WOT from getting to TB (which would influence TB performance on long term for sure)
- Or slam another can :)
Run it 3 months one way and measure the **** you collect, then try it the other way. Only expense will be some more hose.
 

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Ok ... it's a sunny morning, so I double checked it on the car .

The crankcase venting system for our V6/LY7 is %100 like HSV-GTS-300 has explained in above.
PCV orific fitting is on the most corner of RH camshaft cover (US psngr side), a damn small fitting (heater hoses pass above it so you really need attention to see it). Tiny tube goes from this fitting to y-joint branching to intake manifold both sides (red line in HSV's photo). Then there is the breather (fresh air) line from intake tube before TB to fitting on LH camshaft cover (US driver side).

The PCV fitting of 3mm orificed line might be like a GM "allowable controlled" blow-by amount to vent into intake manifold, if blow-by exceeds that, GM system allowed that backflow throw breather line!


Having seen it now, with above argument about on which line to put catchcan, and information provided from GM manual, its to test and decide what line has more flow of blow-bys.
 
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