Thanks for the reply!
With this vc, is all that's needed for pcv the lines and 2 catch cans? Or would we still need something akin to the RB external kit
Aftermarket Valve Cover and PCV
- Thread starter ShocknAwe
- Start date
With this vc, is all that's needed for pcv the lines and 2 catch cans? Or would we still need something akin to the RB external kit
Just to clear something up, this is my understanding:
If you want to retain pcv with an aftermarket VC, you just need a PCV valve with the correct threads/barb in and out, and for those who desire you can run the flapper inline off a 10AN -> 3/4" barb or similar. I already have relocated my flapper to the exhaust outlet of my high can. Works fine.
The high/low side aren't literally divided into sealed sides, calling them this is actually confusing as they should be called the high load and low load valves. One has fumes pushed out on high load and the other has fumes sucked out in vacuum but the fumes come from the same place, the crank case. So nothing is changed as long as there is a pcv valve correctly plumbed and a flapper or vta if you prefer.
The flapper and pcv valve work in opposite directions making them a 'mechanical if/then' statement as stated by @Jason@Propulsive-Dynamics
So be it a vc with the stock cyclone or aftermarket vc without, the function of the pcv is dependent on what valves you have connected and not so much about internal plumbing.
I apologize if I've made any mistakes.
If you want to retain pcv with an aftermarket VC, you just need a PCV valve with the correct threads/barb in and out, and for those who desire you can run the flapper inline off a 10AN -> 3/4" barb or similar. I already have relocated my flapper to the exhaust outlet of my high can. Works fine.
The high/low side aren't literally divided into sealed sides, calling them this is actually confusing as they should be called the high load and low load valves. One has fumes pushed out on high load and the other has fumes sucked out in vacuum but the fumes come from the same place, the crank case. So nothing is changed as long as there is a pcv valve correctly plumbed and a flapper or vta if you prefer.
The flapper and pcv valve work in opposite directions making them a 'mechanical if/then' statement as stated by @Jason@Propulsive-Dynamics
So be it a vc with the stock cyclone or aftermarket vc without, the function of the pcv is dependent on what valves you have connected and not so much about internal plumbing.
I apologize if I've made any mistakes.
Guess I just don't get how to set this up. Anyone feel confident enough to put together a parts list to make this work like stock with a plugged head?
What do you currently have for PCV?
If you are fully stock then just buy a pcv valve. It appears they offer one through radium or you could buy the RB external valve or any others that might do the same job. Route that to your intake manifold, put a catch can in between. You can use any utility port on your intake manifold or buy one of those adapter pieces that connect by the throttle body.
Then for the other valve just run a barb to rubber hose and slip the flapper into it and route the exhaust of that anywhere you want.
I found thread with some information about the pcv system. Helped me, might help someone else... Pictures 
bmw.spoolstreet.com
Dual Catch Can - Why you want to do it
What is a dual catch can? If you have read about the need for doing a walnut blasting to clean the valves... that is what this is all about. The cause of the dirty valves is due to the CCV dumping oily, yucky, blow-by sh$t back into the intake, across the valves and back into the engine to be...
bmw.spoolstreet.com
VTT Cover, Vented Oil Cap, Front port blocked on cover. 2 catch cans. One VTA, One Draws Vacuum from intake manifold with 1 way check valve.
PCV channels in the head that run to the intake ports have been blocked.
Port on Throttle body has also been blocked.
PCV channels in the head that run to the intake ports have been blocked.
Port on Throttle body has also been blocked.
Attachments
Here is my flapper:
You can see it coming out of one of occ:
It just dangles here and has left zero oil residue after about 3000 miles and the can had about 1/2" of fluid:
I need to route it down further or over to my intake somehow. It does smell when I do a pull.
You can see it coming out of one of occ:
It just dangles here and has left zero oil residue after about 3000 miles and the can had about 1/2" of fluid:
I need to route it down further or over to my intake somehow. It does smell when I do a pull.
Is the flapper the same thing as a check valve? Just facing opposite direction as the low side...
Its a two-way swing valve I guess. One direction it opens all the way the other direction is a smaller opening:
Again: The small hole in the flapper valve has this size, because it´s there to regulate the amount of vacuum inside the VC. @doublespaces is totally right, that you can set that system no matter how the internal structure is- but what i don´t understand is, how M18, VTT or anybody else who sells those VC´s doesnt clarify that.
If you delete the flapper valve from the high side and put a check valve (so nothing else then a PCV) into the low load side, you don´t have any restriction of the vacuum that is sucking on the crankcase... IMO that can´t be positive and you should rely on the amount BMW found working good on the engine.
@DaeDoe s System is a system like i see isn´t that good, because ALL of the vacuum will pull on the crankcase...
@doublespaces do i see it right, that you put the flapper valve on the outside of your high side Catch can? Do you have the low load side connected to a vacuum source? If yes that would mean in theory during low load events the vacuum from the low load side does not only pull on the crank case, but also pulls on your high side catch can.
If i would build an PCV System with an upgraded VC i would VTA one side AFTER the Flapper valve and run an PCV Valve or checkvalve in the line on the other side with an Catch Can, which afterwards connects to a vacuum source (TB for example). So it serves the same function as oem: During Low Load there is a vacuum from the TB which pulls the fumes out from the crankcase and provides a steady vacuum in it and during high load there is boost from the TB which doesnt get into the Crankcase because of the PCV/checkvalve and the other side just vent´s to air. Because of the ocrifice in the Flapper Valve on the VTA side, the amount of vacuum from the Catch can side is regulated like it should.
Hope you can understand.
If you delete the flapper valve from the high side and put a check valve (so nothing else then a PCV) into the low load side, you don´t have any restriction of the vacuum that is sucking on the crankcase... IMO that can´t be positive and you should rely on the amount BMW found working good on the engine.
@DaeDoe s System is a system like i see isn´t that good, because ALL of the vacuum will pull on the crankcase...
@doublespaces do i see it right, that you put the flapper valve on the outside of your high side Catch can? Do you have the low load side connected to a vacuum source? If yes that would mean in theory during low load events the vacuum from the low load side does not only pull on the crank case, but also pulls on your high side catch can.
If i would build an PCV System with an upgraded VC i would VTA one side AFTER the Flapper valve and run an PCV Valve or checkvalve in the line on the other side with an Catch Can, which afterwards connects to a vacuum source (TB for example). So it serves the same function as oem: During Low Load there is a vacuum from the TB which pulls the fumes out from the crankcase and provides a steady vacuum in it and during high load there is boost from the TB which doesnt get into the Crankcase because of the PCV/checkvalve and the other side just vent´s to air. Because of the ocrifice in the Flapper Valve on the VTA side, the amount of vacuum from the Catch can side is regulated like it should.
Hope you can understand.
I'm thinking same.
High: vc - flapper - vta
Low: vc - pcv - occ - mani/tb (for vacuum)
Neil
Rob@RBTurbo
Lieutenant
The OE VC has a ton of baffling in it, cyclonic separation, drainback, etc.; even before the PCV functions. None of it is going to be of any real restriction and it of course has a purpose, personally I like it being there but there again it is a function of only the OE Plastic valve cover which also can have it's issues by its material design in itself.
It is going to be interesting to see how much more oil these aftermarket valve covers puke out, most of which with zero baffling and certainly none with any internal separators. But at the end of the day agree to run the same PCV setups that are ran today but expect to catch much more oil in your OCC's as the OE internal "safety nets" are no longer in place, thus OCC separation efficiency is going to be even that much more important.
Some adapters to connect the high side flapper and low side PCV would be a nice touch, and we'd likely place the provision for the high side on the exhaust side back portion of the cover and provision for the low side on the intake side back portion of the cover... and of course size them appropriately.
Rob
It is going to be interesting to see how much more oil these aftermarket valve covers puke out, most of which with zero baffling and certainly none with any internal separators. But at the end of the day agree to run the same PCV setups that are ran today but expect to catch much more oil in your OCC's as the OE internal "safety nets" are no longer in place, thus OCC separation efficiency is going to be even that much more important.
Some adapters to connect the high side flapper and low side PCV would be a nice touch, and we'd likely place the provision for the high side on the exhaust side back portion of the cover and provision for the low side on the intake side back portion of the cover... and of course size them appropriately.
Rob
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We do understand. What we have done when running our dual cans with the Billet VC is introduce a controlled vacuum leak through the "high side" of the can. You have a check valve to prevent boost from entering the crankcase on the low side, but on the high side, the vacuum can escape through the breather or rear inlet depending on how you have it plumbed. Having to pull vacuum through all the baffling in the can/breather etc allows vacuum to exit the crankcase since it's not a sealed system so you do not introduce too much vacuum as some escapes. Is this precise, not really, but we have never had an issue with it. We run it this way on all our cars. Now if someone runs a VTT Billet VC, and wants to plumb it sealed (check valve on the high, and low side), they will need a way to limit vacuum to the crankcase. You can tell you have too much when it sucks past the seals at idle, and you hear a whistling sound. We have some very cool products coming to market in about 30 days one will address regulating vacuum in the crankcase, and complement our existing line-up. If you have any questions, as always [email protected]
Chris
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Negative pressure by itself on the catch can is largely meaningless from where I stand. If anything cfm and velocity would play a more important role here if you're worried about reversion of the oil?
That is how my low side is setup. Except I use a pcv valve and a check valve. The check valve is just to prevent pressurizing the oil filled catch can
The flapper isn't a pressure activated valve so I'm not following you here.
Edit: I suppose I should say, there is likely a cracking pressure but I'm unsure how that is relevant. Perhaps high side catch can design is however?
There’s a super simple solution to that and it has been used on domestics and high power imports for years...its a vacuum break. You set it for the vacuum you don’t want to exceed and it acts just like a bov. If I had to guess, that is what you guys are adding to the line up.
Can someone explain so I can understand.
With a after market valve cover that just has threaded holes in back top for a high/low catchcan,how does that work since theres no passages like in the stock valvecover? Sounds like to me there would be a lot of oil pumping into the catch can for no reason.
With a after market valve cover that just has threaded holes in back top for a high/low catchcan,how does that work since theres no passages like in the stock valvecover? Sounds like to me there would be a lot of oil pumping into the catch can for no reason.
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