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Discussion Starter #1
I just installed a Moroso AOS after ignoring my oily charge pipe for some time. After 100 miles of extremely spirited driving, this is what was in my catch can. Not much! I've heard varying accounts of how much oil has been captured by other members utilizing aftermarket catch cans/AOSs. After running my own AOS with the stock separators in place, it appears that the stock separators work quite well.

Before installing the Moroso unit, I did a boost leak test to see if the stock separators leaked and found no obvious leakage. My compressor is not big enough to maintain high volume constant pressure, so it's a possibility that they leak at high boost. I think boost leaks are the primary reason for some people deleting these from their systems?

From accounts that I've had shared with me, some of the members who have deleted the stock separators were capturing very large volumes of oil in their aftermarket separator. I'm now wondering if it's prudent to eliminate the stock separators?

While I recognize that it's possible that my engine is in amazing shape compared to these other members cars, isn't it more likely that the stock separators work a lot better than is generally thought to be the case?

And just to clear things up…while some will consider it a subject of semantics….
Catch can = empty container with inlets and outlets
Air Oil Separator (A.O.S.) = container with inlets and outlets using a variety of possible mediums/methods to pull oil out of the air that is circulated through it (baffling, filtration media, venturi, centrifugal).


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