RB External PCV Help

[Rob@RBTurbo]

What are the thoughts on the VTT oil cap vent? @Rob@RBTurbo

Biggest fear of something like that is the introduction of another variable- meaning a component that MAY not do precisely what it needs to do spontaneously under many dynamic driving conditions.

However IF it is bullet proof and works flawlessly then we'd still think it would do next to nothing aside under a high load condition where there is no vac assist from say a turbo inlet. This said it seems it could be more of a liability to the system under any other conditions and perhaps better geared towards PCV delete type setups. Ultimately the ONLY time you'd want a breather cap to ever allow ventilation is when under high load and any vac assist is well overcome by a blowby condition, which we believe is the entire premise of the product however are not convinced of the function.

Some testing would be needed to confirm however it could be beneficial at a point where the system really is overtaxed, the engine is degraded, etc... but there again under nearly all other circumstances it really needs to be sealed shut (ie. such as when not equipped) if you want to retain PCV functionality.

In short one who would utilize it should be 100% confident it ONLY operates to the open position when the ventilation system is overtaxed (under high load conditions) and remains completely sealed the rest of the while.

Rob

 

[Jeffman]

I have the all three - the BMS OCC connected to the flapper for high pressure crank case operation, the RB external PCV and Mishimoto OCC for low pressure crank case operation, and finally (just for shits and giggles) a VTT oil cap vent! As far as I can tell that VTT oil cap vent holds a nice vacuum and has NEVER blown open to release any noticeable pressure, despite my trying to blow up my stock turbos at 24 psi.
Any body want to buy a “lightly used” VTT oil cap vent? 50% off list plus shipping. Lol.

 

[BMWE92_Harry]

Is your head ports plugged?

 

[Jeffman]

Nope

 

[fmorelli]

Can I ask why you haven't plugged?

Filippo

 

[Jeffman]

Simply no time to do it, and feeling the time commitment would not be worth it right now.

 

[NoQuarter]

Can I ask why you haven't plugged?

Filippo

Ha!... I keep asking myself that. My valve cover was replaced under a warranty I had. So it is brand new and more importantly not leaking at all. For now, I am happy to maintain that instead of taking it off to plug the head than risk creating a new problem with the valve cover/gasket. Too many other things to do!

 

[Jeffman]

^^ This.

 

[fmorelli]

Well part of why I ask ... I understood that this was a source of oil vapor for the intake, and after all the whole reason for doing all this PCV crap is to solve that. Do you all believe that the oil vapor is negligible at the head passages? I guess I'm of the mind of wanting to solve it once. I plan to walnut blast when I do the low side solution. My expectation is to not have to blast again.

Filippo

 

[Rob@RBTurbo]

Well part of why I ask ... I understood that this was a source of oil vapor for the intake, and after all the whole reason for doing all this PCV crap is to solve that. Do you all believe that the oil vapor is negligible at the head passages? I guess I'm of the mind of wanting to solve it once. I plan to walnut blast when I do the low side solution. My expectation is to not have to blast again.

Filippo

It is not required to plug the head ports with the RB External PCV setup, it will function the same regardless. But not doing as such leaves a vulnerability in place if in the event the valve cover and/or gasket ever become compromised; and with the RB External PCV you CAN plug them and avoid this indefinitely while still getting proper PCV functionality.

Rob

 

[megaman416]

The flapper assembly is a fundamental requirement for the PCV system to operate correctly primarily when operating under low load conditions where the flapper gate will swing shut, but leave a calibrated orifice to bias appropriate airflow through the crankcase which works in unison with the PCV valve. Under high load conditions the flapper gate will swing fully opens, doing nothing other than providing an opening for ventilation to occur. In short leave the flapper in place and functional if you are running a PCV setup.

Rob

Thanks Rob really helpful. On the high side utilizing the factory flapper and a bms can, could I run it to the chargepipe where the meth bung was? There's a 1/8" npt there now assuming that's too small? Would upgrade to a 3/8" or 10AN? Or should I stick to the single turbo filter?

I like the idea of the chargepipe as it would be a cleaner setup...

 

[Rob@RBTurbo]

Thanks Rob really helpful. On the high side utilizing the factory flapper and a bms can, could I run it to the chargepipe where the meth bung was? There's a 1/8" npt there now assuming that's too small? Would upgrade to a 3/8" or 10AN? Or should I stick to the single turbo filter?

I like the idea of the chargepipe as it would be a cleaner setup...

No. Under boost you literally would be turbocharging your crankcase directly... really REALLY bad idea. Please just keep it as directed above, there truly is no need for further thoughts on these things.

 

[megaman416]

No. Under boost you literally would be turbocharging your crankcase directly... really REALLY bad idea. Please just keep it as directed above, there truly is no need for further thoughts on these things.

Got it thanks. Only reason I mentioned it was because the low is going to throttle body. Too much air on the high side got it.

 

[Rob@RBTurbo]

Got it thanks. Only reason I mentioned it was because the low is going to throttle body. Too much air on the high side got it.

Low side goes to intake manifold (between the throttle body blade and intake valves).