RB external PCV setup
- Thread starter TurboMike
- Start date
The RB fitting on the PCV delete side blocks the return back to the oil pan thereby externalizing the PCV altogether. Once externalized, the ccv is vacuum routed back into the throttle body.
We've had these kits in production for over a year now and the only complaint seems to be the lack of catch can adapter for a cleaner install (which we understand but have not had the time to produce). Other than this the feedback has been excellent and everyone seems to be very content and some elated. Up until recently we haven't even had the moment to add them to the website but they are there finally
http://www.rbturbo.com/products/accessories/rb-n54-external-pcv-kit
(FYI we are out of stock currently and another batch is currently being machined)
Did you evaluate concerning pressures in the crankcase?
I installed an relocation inlet kit last week and i am running now VTA on the boost side. Since i think that the boost side is not the biggest reason for dirty valves i started researching about the PCV System and how it works.
Dzenno made a good test in 2011 measuring the pressures in the crankcase with different setups (only boost side), he came to the conclusion, that an OCC does minimize the vacuum in the crankcase which is not really good for the seals etc.
After rethinking it i thought that the low boost side should the more important one.
So my question is:
- do you know that an OCC on the low boost side like your kit is providing does not harm the crankcase pressures?
- What do you advice concerning high boost side, is running VTA ok?
- Why do the head ports need to be tapped? Would this mean without tapping there still is a little bit of oil running through the head ports? How do you know how much runs through the external and how much through the head ports?
- How is it connected to the throttle body?
I am really looking forward to hear your input. Of course any other one can chime in, but i thought adressing the producer would be nice, cause i am sure rob did thought about this things.
Up to now i have the tendency to reroute the high boost side to my Inlet, so that there still is a vacuum. Then using your system with OCC..
Robs system introduces a steady state of vacuum with the 'out' vent line from the OCC taping into the throttle body. Which is exactly what the goal was if I'm understanding it correctly (to remove pressure in the crankcase and valve cover by externalizing the pcv and creating a steady source of vac)
Mine is sitting in my room so to be clear I could be 100% wrong. Anyone correct me if that is the case.
Mine is sitting in my room so to be clear I could be 100% wrong. Anyone correct me if that is the case.
This is how I see this system functioning..
If connected without an OCC it looks like this system functions like the OEM system except that the oil or blow by will enter into the intake manifold via TB vacuum port rather than the 6 ports on the head.
The advantage of this system is that it allows a connection for an OCC which will help trap oil and blow by from reaching the intake system.
The problem with that design to me is that the TB line is not steady state vacuum, it's only under vacuum when you're under idle or deceleration, not acceleration. Under acceleration, when crankcase pressure is probably the highest, the TB line is likely under atmospheric pressure or boost. To truly do the PCV system correctly you need to have a dedicated vacuum pump or vent to atmosphere.
I understand how the System is working.
The question is:
- If the head ports are not tapped there are 2 vac sources: The TB and the Headports. How can we be sure that the vac from TB where the OCC is connected to gets the most blowby? I mean it is written in the description of his set, that it´s function best when head is tapped. But i don´t think much People will tap them so the question is how efficient is the System without tapping?
And:
- What in total do you recommend for PCV Boost Side? Is VTA okay and does not harm the seals and oil drainages to Turbos?
- What side is more important to have vac?
Aaron´s thought are also what i am not sure about- but VTA on the low side is worse than on the boost side i think...
The question is:
- If the head ports are not tapped there are 2 vac sources: The TB and the Headports. How can we be sure that the vac from TB where the OCC is connected to gets the most blowby? I mean it is written in the description of his set, that it´s function best when head is tapped. But i don´t think much People will tap them so the question is how efficient is the System without tapping?
And:
- What in total do you recommend for PCV Boost Side? Is VTA okay and does not harm the seals and oil drainages to Turbos?
- What side is more important to have vac?
Aaron´s thought are also what i am not sure about- but VTA on the low side is worse than on the boost side i think...
That's what the Bms kit that everyone one has been running for years covers. The rb kit was designed because the bms kit only functions under boost. So with the rb and bms kit and 2 catch cans you have vacuum to the crankcase under all conditions like the factory intended but with the added bonus of oil seperation.
Rob@RBTurbo
Lieutenant
This kits operation is very simple actually. All it does is change the vacuum reference point from a path of internal passaging (ie. through PCV valve and via the valve cover to the head ports) to external passaging (ie. through PCV valve and via the hose to the throttle body). The external PCV adapter in itself blocks the standard vacuum flow towards the head ports, but blocking the head will rule out leak vulnerabilities in the valve cover/gasket so it is still recommended to do at the soonest availability. The OEM vent flapper assembly is also retained. This setup does nothing for the high load side, it is low load side only. More can be read here:
http://www.rbturbo.com/products/accessories/rb-n54-external-pcv-kit
We finally have another batch completed- so all that have ordered will be shipping soon (probably after christmas).
Rob
http://www.rbturbo.com/products/accessories/rb-n54-external-pcv-kit
We finally have another batch completed- so all that have ordered will be shipping soon (probably after christmas).
Rob
Ok, so the Adapter blocks flow to the head ports, that is what i get.
Another big question for me, even if it is not directly related to your product, is: Would you recommend going VTA on Boost Side? What Side do you think is the more important one for having a vacuum? Will having no vacuum on Boost Side and Vacuum on Low Load Side with Your external or the OEM System be harmful?
Would love to hear your opinion on this Topic. Cause i do not want to run a System which in any form is potentially harmful to my Motor (VTA like i am running now).
Did you messure the vacuum from TB through an Catch Can like the Mishmoto one with your System?
If i remember the BMS Catch can was adviced on boost side because it seemed the one which has the least restriction for the vacuum- Is this the same Thing for the mishmoto OCC?
I really want to be safe if i will run the external PCV System on low load side, because i think there it is even more important, that the vacuum is save.
Thanks for your answer Rob!
Another big question for me, even if it is not directly related to your product, is: Would you recommend going VTA on Boost Side? What Side do you think is the more important one for having a vacuum? Will having no vacuum on Boost Side and Vacuum on Low Load Side with Your external or the OEM System be harmful?
Would love to hear your opinion on this Topic. Cause i do not want to run a System which in any form is potentially harmful to my Motor (VTA like i am running now).
Did you messure the vacuum from TB through an Catch Can like the Mishmoto one with your System?
If i remember the BMS Catch can was adviced on boost side because it seemed the one which has the least restriction for the vacuum- Is this the same Thing for the mishmoto OCC?
I really want to be safe if i will run the external PCV System on low load side, because i think there it is even more important, that the vacuum is save.
Thanks for your answer Rob!
Rob@RBTurbo
Lieutenant
Rob@RBTurbo
Lieutenant
Just as FYI- I'd highly suggest reading this thread so we are not recreating the discussion wheel:
http://www.n54tech.com/forums/showthread.php?t=35535
We have spent many many hours addressing a ton of questions here already. The end result is this kit works. It takes an OEM PCV scheme and improves significantly upon the largest vulnerabilities. Oil consumption rates are at times improved. Smoking symptoms are at times mitigated or corrected altogether. Large amounts of normally ingested contaminates are caught. Vacuum is retained on the crankcase as it should be (where possible). Many many customers with all walks of life setups are satisfied, several have moved back from a VTA setup and aren't looking back. It's just a win win.
Some others will swear by VTA as that is what they know and it has worked well for them- regardless of the complete removal of any vacuum on the crankcase. That is fine too whatever floats ones boat.
Rob
http://www.n54tech.com/forums/showthread.php?t=35535
We have spent many many hours addressing a ton of questions here already. The end result is this kit works. It takes an OEM PCV scheme and improves significantly upon the largest vulnerabilities. Oil consumption rates are at times improved. Smoking symptoms are at times mitigated or corrected altogether. Large amounts of normally ingested contaminates are caught. Vacuum is retained on the crankcase as it should be (where possible). Many many customers with all walks of life setups are satisfied, several have moved back from a VTA setup and aren't looking back. It's just a win win.
Some others will swear by VTA as that is what they know and it has worked well for them- regardless of the complete removal of any vacuum on the crankcase. That is fine too whatever floats ones boat.
Rob
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Rob, from your testing, does VTA have any negative effects. I assume that when this PCV system was developed, you tested many configurations and were able to see what worked and did not. Also, any testing resulting in gains due to reduced blow by or crankcase pressures?
Just as FYI- I'd highly suggest reading this thread so we are not recreating the discussion wheel:
http://www.n54tech.com/forums/showthread.php?t=35535
We have spent many many hours addressing a ton of questions here already. The end result is this kit works. It takes an OEM PCV scheme and improves significantly upon the largest vulnerabilities. Oil consumption rates are at times improved. Smoking symptoms are at times mitigated or corrected altogether. Large amounts of normally ingested contaminates are caught. Vacuum is retained on the crankcase as it should be (where possible). Many many customers with all walks of life setups are satisfied, several have moved back from a VTA setup and aren't looking back. It's just a win win.
Some others will swear by VTA as that is what they know and it has worked well for them- regardless of the complete removal of any vacuum on the crankcase. That is fine too whatever floats ones boat.
Rob
Have you done any research in valve cover breathers?
Rob@RBTurbo
Lieutenant
I'd suggest you guys do some reading on basic PCV understandings. You can find some really light reading here under PCV wiki:
https://en.wikipedia.org/wiki/Crankcase_ventilation_system
As you can see VTA is essentially the 1950's style "road draft tube". It is nothing aside an opening for an engine to puke up toxins into the atmosphere or oils onto the roadways (yes your VTA setups will make a mess all over). For some dedicated racers, sure, it'll get the job done but it is not efficient in anyway whatsoever aside for just being simple/cheap/easy.
If you read a bit closer you will see that due to the vacuuming effect of the PCV valve (in low load conditions) oil condition and crankcase cleanliness are also extended. Again if you are a dedicated racer and rebuild every season or so, or maybe only drive a limited miles per year, or enjoy breathing hydrocarbons to get the day going, then sure great knock yourself out. This however doesn't meet the demographic of 99% of this platform. Many want efficiencies in their daily driver or street car. Many want oil cleanliness and longer change intervals. Many want the constant vacuum draw and filtration with through the crankcase to keep it as tidy as possible. There are some substantial reasons to believe the vacuum applied to the engine in most everyday driving scenarios also extend engine life through better piston ring seal (you all can google around the perks of vacuum on piston ring seal if you'd like). There even maybe some who appreciate all of the perks and the icing on the cake is that it is better for the environment. The perks of retaining a PCV system, IMHO, outweigh any drawback (vs. VTA) in every shape and form aside for system simplicity. So for us to go back in technology 60 years and test why a VTA setup is still as ineffective today as it was then is beyond me, especially when there's already a better solution in hand.
Again if you are a hardcore racer, or maybe you rebuild often, or never drive your car, or love changing your oil much earlier than necessary, or love the Hydrocarbon smell in your cockpit or dripping more oil on the streets (than you would otherwise); then you can just run VTA and be happy with it. For the rest we would suggest running some sort of PCV system. Once again this external PCV is nothing of the rocket science nature- it is simply a means to take a more reliable vacuum path than via the vulnerable valve cover passageways and valve cover gasket. This and it allows you to insert a OCC to catch things that would've otherwise been recycled back through the engine.
Rob
https://en.wikipedia.org/wiki/Crankcase_ventilation_system
As you can see VTA is essentially the 1950's style "road draft tube". It is nothing aside an opening for an engine to puke up toxins into the atmosphere or oils onto the roadways (yes your VTA setups will make a mess all over). For some dedicated racers, sure, it'll get the job done but it is not efficient in anyway whatsoever aside for just being simple/cheap/easy.
If you read a bit closer you will see that due to the vacuuming effect of the PCV valve (in low load conditions) oil condition and crankcase cleanliness are also extended. Again if you are a dedicated racer and rebuild every season or so, or maybe only drive a limited miles per year, or enjoy breathing hydrocarbons to get the day going, then sure great knock yourself out. This however doesn't meet the demographic of 99% of this platform. Many want efficiencies in their daily driver or street car. Many want oil cleanliness and longer change intervals. Many want the constant vacuum draw and filtration with through the crankcase to keep it as tidy as possible. There are some substantial reasons to believe the vacuum applied to the engine in most everyday driving scenarios also extend engine life through better piston ring seal (you all can google around the perks of vacuum on piston ring seal if you'd like). There even maybe some who appreciate all of the perks and the icing on the cake is that it is better for the environment. The perks of retaining a PCV system, IMHO, outweigh any drawback (vs. VTA) in every shape and form aside for system simplicity. So for us to go back in technology 60 years and test why a VTA setup is still as ineffective today as it was then is beyond me, especially when there's already a better solution in hand.
Again if you are a hardcore racer, or maybe you rebuild often, or never drive your car, or love changing your oil much earlier than necessary, or love the Hydrocarbon smell in your cockpit or dripping more oil on the streets (than you would otherwise); then you can just run VTA and be happy with it. For the rest we would suggest running some sort of PCV system. Once again this external PCV is nothing of the rocket science nature- it is simply a means to take a more reliable vacuum path than via the vulnerable valve cover passageways and valve cover gasket. This and it allows you to insert a OCC to catch things that would've otherwise been recycled back through the engine.
Rob
I also talked to Andy from AD-E..
He said a lot of different things comparing to rob´s statements.. i am a little bit stuck between the chairs..
He says:
There is no vacuum during high load events, so no need to connect the boost side to the intake with or without the OCC. He says only a large vacuum pump would provide pulling a vacuum, since there is enough pressure from the blowby based on the high load in the engine in this moment and with exhaust or intake you would not have any vacuum higher than the pressure flowing out of the engine.
What i do not understand (i read all of the linked threads):
You advice a high flowing catch can for the boost side and an high filtering one for the low load side. You say that the vacuum during low load and idle is important- but also state that you need a high flowing catch can for the boost side in order to still have the vacuum making it to the VC. If vacuum on the low load side is also important why would you advice a high filtering occ on this side? A high filtering OCC seems to not flow enough for providing vacuum?
I get everything you are saying:
- OCC is superior than no OCC, cause you catch a lot of things which without get stuck in the valves.
- VTA is bad or an outdated version of crankcase ventilation
But what i want to know is not why you run the system. More it is about vacuum and your thoughts about it:
On which side the vacuum is important? High or low load side? And if you think it is important on both sides, why running different OCC´s on both sides?
If the Vacuum on low and high load side is negligible than why not doing it like AD-E and deleting the low load side in order to run all the gases through the high load side with OCC, VTA or whatever?
He said a lot of different things comparing to rob´s statements.. i am a little bit stuck between the chairs..
He says:
There is no vacuum during high load events, so no need to connect the boost side to the intake with or without the OCC. He says only a large vacuum pump would provide pulling a vacuum, since there is enough pressure from the blowby based on the high load in the engine in this moment and with exhaust or intake you would not have any vacuum higher than the pressure flowing out of the engine.
What i do not understand (i read all of the linked threads):
You advice a high flowing catch can for the boost side and an high filtering one for the low load side. You say that the vacuum during low load and idle is important- but also state that you need a high flowing catch can for the boost side in order to still have the vacuum making it to the VC. If vacuum on the low load side is also important why would you advice a high filtering occ on this side? A high filtering OCC seems to not flow enough for providing vacuum?
I get everything you are saying:
- OCC is superior than no OCC, cause you catch a lot of things which without get stuck in the valves.
- VTA is bad or an outdated version of crankcase ventilation
But what i want to know is not why you run the system. More it is about vacuum and your thoughts about it:
On which side the vacuum is important? High or low load side? And if you think it is important on both sides, why running different OCC´s on both sides?
If the Vacuum on low and high load side is negligible than why not doing it like AD-E and deleting the low load side in order to run all the gases through the high load side with OCC, VTA or whatever?
Rob@RBTurbo
Lieutenant
He is correct although that is a high load discussion. The only way to get any appreciable amount of vacuum on the crankcase during high loads is with an external vacuum pump. This is a different discussion altogether and it becomes a very expensive system that is quite unnecessary for your typical street machine or daily driver.
What we are discussing here are the benefits of a PCV system, which operates in all conditions aside for high load (ie. under boost), and those benefits are eliminated if you remove the PCV system in favor of an all around VTA setup. More specifically this thread is about running the PCV system externally, as the OEM PCV system is Internal and has some vulnerabilities and can be at times unreliable.
Regarding me saying you are required to run an OCC on either side- not true. I am saying that if YOU want to you can. You can also run neither. You can also run one. It does not matter if you do any or all, it just depends if you want to be able to intercept oils/contaminates and catch them- or recycle them back through the engine. This is all up to the vehicle owners wishes. If you want to run one it seems that the low side OCC does a LOT more of the catching, so I'd run that one before the high side OCC (but you need an external PCV to do this). If you DO decide on running an OCC on the high side, then make sure it is not restrictive so under high loads the ventilation can be as free flowing as possible (ie. the BMS unit is very high flowing). The high flow side is mostly independent from the low load side, and its primary function is for when you are in high load (ie. boost).
Thanks,
Rob
What we are discussing here are the benefits of a PCV system, which operates in all conditions aside for high load (ie. under boost), and those benefits are eliminated if you remove the PCV system in favor of an all around VTA setup. More specifically this thread is about running the PCV system externally, as the OEM PCV system is Internal and has some vulnerabilities and can be at times unreliable.
Regarding me saying you are required to run an OCC on either side- not true. I am saying that if YOU want to you can. You can also run neither. You can also run one. It does not matter if you do any or all, it just depends if you want to be able to intercept oils/contaminates and catch them- or recycle them back through the engine. This is all up to the vehicle owners wishes. If you want to run one it seems that the low side OCC does a LOT more of the catching, so I'd run that one before the high side OCC (but you need an external PCV to do this). If you DO decide on running an OCC on the high side, then make sure it is not restrictive so under high loads the ventilation can be as free flowing as possible (ie. the BMS unit is very high flowing). The high flow side is mostly independent from the low load side, and its primary function is for when you are in high load (ie. boost).
Thanks,
Rob
Ok, so you say the OCC on the High side should be as free flowing as possible to let the motor "breathe" freely, not because of the vacuum?
If the PCV gets deleted without an external setup the gases flow through the high load side no matter what load situation, at least that is how i understood andy.
I know you are saying you can do everything or nothing OCC wise, but one of the biggest advantages of running low load side external is that you can use a catch can?
Again: Does the crankcase see vacuum on low load events asides boost conditions? And do you think the vacuum is important? If yes the mishmoto high filtration occ would be the wrong decision for use on this side, cause it hinders the vacuum getting "up" to the crankcase?
I know i am mixing the topics a little bit, but i think in the future the people will think about both sides, at least that is what they should do!
I hope you understand me, sometimes language barriers are a little bit challenging.
Thanks!
If the PCV gets deleted without an external setup the gases flow through the high load side no matter what load situation, at least that is how i understood andy.
I know you are saying you can do everything or nothing OCC wise, but one of the biggest advantages of running low load side external is that you can use a catch can?
Again: Does the crankcase see vacuum on low load events asides boost conditions? And do you think the vacuum is important? If yes the mishmoto high filtration occ would be the wrong decision for use on this side, cause it hinders the vacuum getting "up" to the crankcase?
I know i am mixing the topics a little bit, but i think in the future the people will think about both sides, at least that is what they should do!
I hope you understand me, sometimes language barriers are a little bit challenging.
Thanks!
Rob@RBTurbo
Lieutenant
Yes, the high load side has no vacuum available of any real significance. The OEMs route it back into the turbo inlet to help provide a bit of vacuum, but the vacuum pull is barely worth mentioning. Exhaust scavenging has also been used, but this is stinky and still offers no real significant vacuum. As stated above the only way to get a desirable vacuum at high load is with an external vacuum pump, which is often done by extreme racers. The OEM method recycles the oils/vapors back through the turbo tract and re-ingest it through the engine, which is better for mother earth alongside with giving a tid bit of vacuum.
Inserting a High Side OCC can can help collect the oils so that they are not recycled and this has been done for many years on the N54. What has NOT been done is inserting an OCC on the low load side due to the fact it was not possible with the internal PCV system design. What was found was that the external PCV OCC's are catching a LOT of contaminants, which is precisely what we had expected based on our studies and observations of the internal PCV system vs. Intake valve contamination. If one were to dissect the N54 valve cover, they'd see why the back 3 cylinder Intake valves are the ones that are usually in the most need of cleaning- and that is because the Internal PCV system delivers vacuum to a particular cylinder order (Typical contamination order: Cylinder 5, Cylinder 4 and 6, Cylinder 3, Cylinder 2, and finally Cylinder 1).
In conclusion yes vacuum is present under low load scenarios with the PCV system retained (ie. idle, cruise, decel, etc). This consistent vacuum keeps the crankcase clean, and is almost always working for you without you even knowing. Crankcase "vacuuming" is important in a daily driver and daily drivers spend the extreme vast majority of their life in low load conditions, so there is no reason to move backwards and delete it (and have no vacuum at all in any condition).
Inserting a High Side OCC can can help collect the oils so that they are not recycled and this has been done for many years on the N54. What has NOT been done is inserting an OCC on the low load side due to the fact it was not possible with the internal PCV system design. What was found was that the external PCV OCC's are catching a LOT of contaminants, which is precisely what we had expected based on our studies and observations of the internal PCV system vs. Intake valve contamination. If one were to dissect the N54 valve cover, they'd see why the back 3 cylinder Intake valves are the ones that are usually in the most need of cleaning- and that is because the Internal PCV system delivers vacuum to a particular cylinder order (Typical contamination order: Cylinder 5, Cylinder 4 and 6, Cylinder 3, Cylinder 2, and finally Cylinder 1).
In conclusion yes vacuum is present under low load scenarios with the PCV system retained (ie. idle, cruise, decel, etc). This consistent vacuum keeps the crankcase clean, and is almost always working for you without you even knowing. Crankcase "vacuuming" is important in a daily driver and daily drivers spend the extreme vast majority of their life in low load conditions, so there is no reason to move backwards and delete it (and have no vacuum at all in any condition).
