Serial Jvcomm32. It seems to me the more boost you run and more power you make the more pressure can build up inside your engine thus you need a more adequate catch can system to let your engine properly vent to help avoid blow by.... Sorta but not really. Pressure still wants to go from high to low to equalize.

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So a vented can allows all that high pressure to leave. The 2 plugs on the back of the block are still the restricted area. The Art Of Dying Peter Fenwick Pdf Writer. Doesn't matter if you put a huge catch can vs a small catch can.

Its still going through the two small plugs on the back. This is why you see people with lines running to the valve cover as well. How big of catch can do you need? It all depends how good the rings are and how hard you drive the car for x period. The harder and longer its driven the more oil that is being vaporized. The best way however is to seal the can system and run a slash cut on the exhaust to suck the gas out.