[Elite Engineering]

A breather cap, while the unit you have has a ball valve to prevent unmetered air from entering, does just the opposite of what a proper PCV or crankcase evacuation system needs to function properly. You never want to vent to the engine compartment for several reasons, safety being #1. Flammable vapors vented into a hot engine compartment create an extremely dangerous fire risk. From hot headers to stray spark. Today’s GDI engines experience an excessive amount of raw fuel pushed past the rings into the crankcase, and mixed with the oil vapors create a very volatile mix of flammable/explosive gasses and that is part of why no form of Professional Racing does this antiquated way of dealing with pressure. All now use a vacuum system on the crankcase so pressure cannot build in the first place. Back in the 1960's-1980's venting was universal for racing applications but the safety aspects and the negative impact on everything from power produced in the short term, and excessive wear and damage to internal parts for the long term, dictated using science and technology for a far better solution. But the aftermarket street crowd has taken this outdated method and has ignored all aspects of a proper crankcase evacuation system resulting in tons of confusion and premature engine failures.

All PCV systems have several functions that are for engine longevity and only one is emissions related. Every ICE (internal combustion engine) produces some blow-by. And here is where the self-taught assumptions come into play, most tuner shops simply stop the thought process at the pressure that results. They never wonder what is contained in that blow-by and how it affects the engine. So first, is piston ring seal. Today’s low tension piston rings are very thin and require pressure above them and suction below to maintain stability and proper seal as this holds them against the ringlands. When pressure builds, it pushes the rings up from the bottom and they enter a state of rapid vibration known as ring flutter. This increases blow-by and decreases power made. So, a negative in every way. But venting for the reasons already listed above never results in zero pressure in the crankcase so it is a very poor way to address this. The stock routing this pressure releases into the main intake air tube so no flammable vapors escape into the engine compartment. That is fine with the average daily driver that rarely sees hard acceleration or WOT operation. But a proper system maintains vacuum suction on the crankcase at all times. Pressure can never build when a proper amount of vacuum suction is pulled but the stock PCV systems only use intake manifold vacuum for this suction, and when accelerating or at WOT, there is no IM vacuum present, and this is when pressure will build. So, the simplified thinking is open the crankcase and vent as they used to do in the "old days". But that brings us to the next function. Contained in the blow-by are these substances:
Water, Acids, Raw Fuel, and abrasive particulate matter (ash, soot, and carbon). These are all harmful to the engine attacking the metals, causing far more wear and overwhelming the engine oil’s ability to protect. Today’s full synthetics don't so much "wear out" but become overwhelmed with these contaminants. If not flushed and removed (sucked out/evacuated) they quickly settle and accumulate mixing with the oil. So, the incoming fresh filtered MAF metered air is drawn from the main intake air tube, and this creates a direct path for oil to simply be drawn into the air intake and thus the supercharger. So, our billet CSS has a internal coalescing chamber with stainless mesh coalescing media to trap that oil if pressure exceeds the vacuum generated by our billet Venturi Vacuum Generator. It generates from 7-14" of vacuum so when the IM vacuum drops, the Venturi takes over providing full time vacuum at sufficient levels to prevent pressure from building to begin with. The check valves prevent any pressure back flow and gives the same benefits as a belt driven vacuum pump system, but for the street (except CA). So yes, you do need the CSS to prevent what you’re experiencing.

Let me know if you have more questions as this has not been taught in decades and very few understand it outside of the Automotive Engineering or Professional racing World.

[Deacon Blues]

If I understand correctly, this is the justification for the catch can or some similar apparatus?

[dreksnot]

So, this Venturi Vacuum Generator would be the Catch Cans vacuum source connection versus somewhere like behind the throttle body, as it’s always seeing intake air pulled across it creating vacuum to the crankcase. I can see this working as long as the catch can is ++effective and doesn't allow any vapor into that inlet source stream. If installed before turbos, that wouldn’t be good over time I wouldn’t think.

[ctrlz]

Originally Posted by Elite Engineering

Let me know if you have more questions as this has not been taught in decades and very few understand it outside of the Automotive Engineering or Professional racing World.

Very cool explanation, and we have had several questions recently regarding PCV systems in high output applications.
As you can see by the initial replies, a lot of the questions come down to, "How do I plumb this?"
Catch cans, vents, check valves, vacuum generators... where does it all go, what bits are essential, and which are optional?
And then in high output situations there can be new requirements for tubing diameter and wall strength to prevent collapse.

[Elite Engineering]

Depends on if a LS based or LT based engine, and if FI and what type (turb/centri or a top mount).

All will use the intake manifold vacuum for evacuation when not in boost, or for a NA engine for idle, light cruise, and deceleration when vacuum is present.

The special checkvalves will prevent any back-flow or boost from entering the crankcase from the intake charge. And any time the throttle is open due to reversion pulses.

The in boost, or during acceleration the primary valve closes and the secondary valve opens to use the Venturi Vacuum Generator to take over supplying vacuum suction. It is installed either just upstream of the throttle body for NA, and Top Mount blowers, and at the turbo or centri head unit inlet for any that pressurize the IM.

As all is under vacuum suction, the hose we supply is emissions rated with the strong sidewall with the Barricade hose legal in all 50 States. So that's standard with our systems vs we see many use plain fuel line that is prone to collapse.

The LT engines PCV system works as follows:

Filtered fresh MAF metered air enters from the main intake air tube. It then enters the black plastic box on the passenger side front of the engine. This also works to trap oil when accelerating and there is no vacuum present as the stock system only uses IM vacuum. Oil vapor can still be pushed past this and backwards into the main air intake. So full time vacuum is what's really lacking. And ask questions for any specific application and we can post pictures and diagrams.

From there it is drawn into both valve covers and it travels past the rocker arms and down each sides oil returns into the main portion of the crankcase flushing and making up for the foul contaminant laden vapors being evacuated (sucked out) the valley chamber and out the PCV cartridge.

So as these tests done independently show, our Patented E2-X and E2-X Ultra models trap nearly all of the oil and the other substances you don't want ingested. In fact 90-95% plus vs all of these "catchcans" people are buying that only trap 15-20% and allow the rest to pass through the can and still be ingested. As no one ever wonders "how much is getting past a can" they simply see gunk caught and assume it is catching it all when that is far from reality:
And anyone can conduct this same test to see first hand:




Elite Engineering E2-X vs Mightymouse Catch Can Shoot Out
In this video I compare the Elite Engineering E2-X catch can with the MightyMouse catch can that has the new super centre in it. I want to see which one is better at trapping oil. I also run an APEX catch can during the test to evaluate the catch can design and how effective it is at trapping oil. I conducted the test by running each can for ...
www.youtube.com


Jason
Elite Engineering USA
Engineering and Technical Support

[Elite Engineering]

Here's another helpful video as well: