Boost into the crankcase is bad
06-11-2006, 08:32 AM
#61
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Originally Posted by jakub2000,Jun 10 2006, 12:56 AM
...I removed the secondary vacuum system since the AEM EMS does not support it...
do I need to put something on the front breather as well? I run it nacked open for over a year, just wanted to put a small filter on it.
Boost should not come FRom the intake manifold through the PCV INTO the crank case, so I will install it in a way where it flows only FROM the engine, INTO the manifold, but blocks the flow the other way around, correct?
06-12-2006, 08:59 AM
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Originally Posted by gary_phd,Jun 11 2006, 08:16 AM
It's the pressure build up that you need to worry about, which could damage your engine. If you use the two Krankents, you don't have to worry about pressure build up.
In short, if you dont want boost in your crank case, put the krank vent in the back(pcv area)....if you want to get the "vacuum" that everyone is raving about, get the krank vent installed on the front as well, just keep in mind that you would lose an important function of the system, being able to take in fresh air. Is this important? Well, car manufacturers have been using this method for 20+ yrs or so....
But i dont see anything wrong with letting the system run the way its been designed. the important thing is preventing boost from entering your krank case. And that sludge that those links were talking about was referring to sludge in the crankcase, not the manifold.
06-12-2006, 09:11 AM
#64
that pressure will still exit out of the front or the back exits
In short, if you dont want boost in your crank case, put the krank vent in the back(pcv area)....
if you want to get the "vacuum" that everyone is raving about, get the krank vent installed on the front as well,
06-12-2006, 11:59 AM
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Originally Posted by xviper,Jun 12 2006, 09:11 AM
But according to the scan I put up, air also "enters" that front breather.
The front breather is open to atmosphere. It shouldn't have any affect on the vacuum as seen at the PCV valve.
The front breather is open to atmosphere. It shouldn't have any affect on the vacuum as seen at the PCV valve.
http://members.rennlist.com/pbanders/PCV.htm
" If the blow-by volume exceeds the ability of the PCV valve to draw in the vapors, the excess blow-by flows back through the crankcase fresh air intake system to the air cleaner box, where it is pulled through the throttle body and into the cylinders." ---- this usually happens during full throttle runs..(Very Low Manifold Vacuum, High Crankcase Pressure) This mode corresponds to heavy load to full-load conditions.
about the front breather, by having a krank vent installed, it actually no longer becomes a breather, since it can no longer take any air in, just out. I'd recommend to just put the krank vent in the back, or block it off like in xvipers catch can set up. voila, no boost in the crank case.
06-12-2006, 01:43 PM
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Originally Posted by ex-eclipse,Jun 12 2006, 03:27 PM
Would this set up let the engine opperate correctly with out allowing boost into the crank case?
Their loss though. 
06-12-2006, 01:53 PM
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I realize that. But my reply still stands. Your engine will run, but your catch can won't catch anything, and you are poluting the atmosphere through the front valve cover breather.
06-12-2006, 02:01 PM
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Wow, I am realy confused now. I thought that the front breather pulled in fresh air while the back (pcv) vented out the blow-by. If oil vapor comes out the front vent, than how come it is never oily or dirty like the inside of the manifold is? fperra, I'm not saying you dont know what you are talking about, I am just trying to understand this so I can fix my car too.