Aftermarket Valve Cover and PCV

[MDORPHN]

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.

As I understand it (and I'm not a tech), the PCV system must do different things depending on whether there is positive or negative pressure in the crankcase. One "function" deals with low load when off boost and the other on high load when positive pressure is present. So the low side is regulating vacuum and the high side is regulating boost. For this reason, there are different components/plumbing needs for each.

Neil

 

[twinturbos]

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.

Do you have a build thread ? I would like to see more pics of your engine bay.

 

[Rob@RBTurbo]

Sounds like to me there would be a lot of oil pumping into the catch can for no reason.

You are likely very correct about the more oil pumping out, as for the reason it is for the trade to the aluminum VC. As is often with modifications, you may trade in one problem for another. Ideally some of those out there running one of these valve covers, with some amount of significant usage, can speak up about what they have seen from their real world experience.

 

[Chris@VargasTurboTech]

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.

We have had them drawn in CAD for over a year, just never bothered to get them done. It's not really needed, and making an MOQ 100 part 5-10 people may realistically buy is not very cost effective. At this point we decided to pull the trigger, and they can sit on the shelf if need be. They are designed to work specifically with our modular catch cans, and Billet VC, so they can be used across our line-up.

Chris

 

[doublespaces]

We have had them drawn in CAD for over a year, just never bothered to get them done. It's not really needed, and making an MOQ 100 part 5-10 people may realistically buy is not very cost effective. At this point we decided to pull the trigger, and they can sit on the shelf if need be. They are designed to work specifically with our modular catch cans, and Billet VC, so they can be used across our line-up.

Chris

Want to drop some info in a new thread? I'm interested if the flapper can be eliminated. Would like to see the progressive nature of the relief and how it operates but also how it would fit into my setup.

Do you have a build thread ? I would like to see more pics of your engine bay.

2009 E93 ADE Single Turbo Build

EDIT: I've added a guide on how to install the AD Engineering Single Turbo Kit in the document section: https://bmw.spoolstreet.com/documents/ad-engineering-single-turbo-install-diy.29/ So I received my AD-E Single Turbo kit in the mail today from @AD-ENG and everything seems to be in order. I...

bmw.spoolstreet.com

 

[Chris@VargasTurboTech]

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.

We can help with this. I think the first flaw is you are misunderstanding what is going under the valve cover. There is no oil "pumping" in there. What you have is oil mist created by blow by and some other factors, you also have crankcase gases that escape past the piston rings, you have some moisture as the engine transitions from cold to hot, and back again depending on Ambient temp, etc. When putting the valve cover (crankcase) under vacuum at idle this purges the things described previously by pulling them out with the vacuum. Think about it this way, you have a clear plastic box that is sealed. Put some steam in there, or smoke of some kind, now attach a vacuum source to it and watch what it does when its turned on. It's going to pull air out of the box, but its also going to pull the smoke and steam out as well as they mix with the air. Now if the vacuum pump does not have a filter on it, the inside of the vacuum pump will become filled with the oil, and water from the steam and vapors pulled from the box. Now imagine your engine is that vacuum source pulling these oil vapors from the box. The catch can is designed to be in the middle and filter those things out. This is why catch cans have many small holes or baffles, or some sort of material insides to separate the fluids from the gas. That falls to the bottom, instead of being sucked into the engine, and you can drain it when it gets full. All a catch can really is is a filter for your crankcase.

With the CNC valve cover, you get rid of the factory cyclonic filter in the VC, and you move this filtration to the OCC. This is where having two cans is good, as you have double the filtration. Even with the CNC VC we have never seen our cans even get 1/4 full of oil, but we will see quite a bit of milkshake looking stuff, which is a mixture of the oil vapor, water vapor, fuel vapor etc. Without the cans, all that would be getting sucked into the engine, and burned. Oil drastically increases your chance of knock, and should be avoided to the best you can. Hence why you run an OCC. This is obviously a simplified version of a PCV/CCV system, but hopefully, it helps you understand it more, and explains why even with no baffle in the VC the cans are doing the baffling for you.

Chris

 

[Chris@VargasTurboTech]

Want to drop some info in a new thread? I'm interested if the flapper can be eliminated. Would like to see the progressive nature of the relief and how it operates but also how it would fit into my setup.

No sir, we like to announce things as we release them. We will make a promo thread once they are done.

 

[BOosted 335i]

We can help with this. I think the first flaw is you are misunderstanding what is going under the valve cover. There is no oil "pumping" in there. What you have is oil mist created by blow by and some other factors, you also have crankcase gases that escape past the piston rings, you have some moisture as the engine transitions from cold to hot, and back again depending on Ambient temp, etc. When putting the valve cover (crankcase) under vacuum at idle this purges the things described previously by pulling them out with the vacuum. Think about it this way, you have a clear plastic box that is sealed. Put some steam in there, or smoke of some kind, now attach a vacuum source to it and watch what it does when its turned on. It's going to pull air out of the box, but its also going to pull the smoke and steam out as well as they mix with the air. Now if the vacuum pump does not have a filter on it, the inside of the vacuum pump will become filled with the oil, and water from the steam and vapors pulled from the box. Now imagine your engine is that vacuum source pulling these oil vapors from the box. The catch can is designed to be in the middle and filter those things out. This is why catch cans have many small holes or baffles, or some sort of material insides to separate the fluids from the gas. That falls to the bottom, instead of being sucked into the engine, and you can drain it when it gets full. All a catch can really is is a filter for your crankcase.

With the CNC valve cover, you get rid of the factory cyclonic filter in the VC, and you move this filtration to the OCC. This is where having two cans is good, as you have double the filtration. Even with the CNC VC we have never seen our cans even get 1/4 full of oil, but we will see quite a bit of milkshake looking stuff, which is a mixture of the oil vapor, water vapor, fuel vapor etc. Without the cans, all that would be getting sucked into the engine, and burned. Oil drastically increases your chance of knock, and should be avoided to the best you can. Hence why you run an OCC. This is obviously a simplified version of a PCV/CCV system, but hopefully, it helps you understand it more, and explains why even with no baffle in the VC the cans are doing the baffling for you.

Chris

Thanks for explaining.

 

[doublespaces]

Made this mashup of photos:

 

[Rob@RBTurbo]

We can help with this. I think the first flaw is you are misunderstanding what is going under the valve cover. There is no oil "pumping" in there. What you have is oil mist created by blow by and some other factors, you also have crankcase gases that escape past the piston rings, you have some moisture as the engine transitions from cold to hot, and back again depending on Ambient temp, etc. When putting the valve cover (crankcase) under vacuum at idle this purges the things described previously by pulling them out with the vacuum. Think about it this way, you have a clear plastic box that is sealed. Put some steam in there, or smoke of some kind, now attach a vacuum source to it and watch what it does when its turned on. It's going to pull air out of the box, but its also going to pull the smoke and steam out as well as they mix with the air. Now if the vacuum pump does not have a filter on it, the inside of the vacuum pump will become filled with the oil, and water from the steam and vapors pulled from the box. Now imagine your engine is that vacuum source pulling these oil vapors from the box. The catch can is designed to be in the middle and filter those things out. This is why catch cans have many small holes or baffles, or some sort of material insides to separate the fluids from the gas. That falls to the bottom, instead of being sucked into the engine, and you can drain it when it gets full. All a catch can really is is a filter for your crankcase.

With the CNC valve cover, you get rid of the factory cyclonic filter in the VC, and you move this filtration to the OCC. This is where having two cans is good, as you have double the filtration. Even with the CNC VC we have never seen our cans even get 1/4 full of oil, but we will see quite a bit of milkshake looking stuff, which is a mixture of the oil vapor, water vapor, fuel vapor etc. Without the cans, all that would be getting sucked into the engine, and burned. Oil drastically increases your chance of knock, and should be avoided to the best you can. Hence why you run an OCC. This is obviously a simplified version of a PCV/CCV system, but hopefully, it helps you understand it more, and explains why even with no baffle in the VC the cans are doing the baffling for you.

Chris

There is no doubt that there is no direct pumping out of oil- surely that was more of a figure of speech. Also good explanations, but to insinuate that the cyclonic separators/drainback inside the OE valve cover operate with no efficiency has to be a bit misleading. While it is true that a double inline OCC can setup (both on low side only) would probably mitigate this loss since there is twice the separation hardware, that would mean now many would be wanting to run 3 OCC's if you still include the high side OCC into the mix. Also as a side note a large variable into the collection in these low side OCC's is the vacuum applied or volume flow through the system, if any, which is worth considering when discussing how much a single sample has collected (or not collected).

My personal past experiences with engines and aftermarket valve covers have shown that without proper baffling (which most do not), that itself can lead to excess oil finding its way in areas it should've never been in the first place... making it quite easy to find its way out into the atmosphere (in direct VTA) or into OCC's on their way to ventilation. So it stands to reason that without any baffling, nor the extra cyclonic separators, that in the same PCV environment from a flow perspective that oil vapors finding the way out of the Valve cover would if anything exponentialize. Chances are this is and has already been noticed and making new parts is the next course of action for remedy, but a sample of users would have to chime in with their feedback with setup descriptions to have a clearer picture.

IMO it is a bummer the OE valve cover is plastic and of course it has its drawbacks with a relatively high failure rate... but it sure would be nice to keep some of the attributes it has in place as well to minimize the mess in the engine bay with more and more external hardware when moving to an aftermarket VC.

Rob

 

[GreyNBlueE92]

There is no doubt that there is no direct pumping out of oil- surely that was more of a figure of speech. Also good explanations, but to insinuate that the cyclonic separators/drainback inside the OE valve cover operate with no efficiency has to be a bit misleading. While it is true that a double inline OCC can setup (both on low side only) would probably mitigate this loss since there is twice the separation hardware, that would mean now many would be wanting to run 3 OCC's if you still include the high side OCC into the mix. Also as a side note a large variable into the collection in these low side OCC's is the vacuum applied or volume flow through the system, if any, which is worth considering when discussing how much a single sample has collected (or not collected).

My personal past experiences with engines and aftermarket valve covers have shown that without proper baffling (which most do not), that itself can lead to excess oil finding its way in areas it should've never been in the first place... making it quite easy to find its way out into the atmosphere (in direct VTA) or into OCC's on their way to ventilation. So it stands to reason that without any baffling, nor the extra cyclonic separators, that in the same PCV environment from a flow perspective that oil vapors finding the way out of the Valve cover would if anything exponentialize. Chances are this is and has already been noticed and making new parts is the next course of action for remedy, but a sample of users would have to chime in with their feedback with setup descriptions to have a clearer picture.

IMO it is a bummer the OE valve cover is plastic and of course it has its drawbacks with a relatively high failure rate... but it sure would be nice to keep some of the attributes it has in place as well to minimize the mess in the engine bay with more and more external hardware when moving to an aftermarket VC.

Rob

Thoughts on running an Air oil separator to bring back some baffling?

 

[Rob@RBTurbo]

Thoughts on running an Air oil separator to bring back some baffling?

You mean like an OCC on the low side? Yeah, you normally will need one even outside of the OE baffling if you want to catch those oil vapors that otherwise get by even an OE baffled/cylconic separated VC. The thought is that a NON-OE, non-baffled, and non-cyclonic separated VC (like those in the N54 aftermarket) will cause much more collection in the same environment.

Thanks,
Rob

 

[GreyNBlueE92]

You mean like an OCC on the low side? Yeah, you normally will need one even outside of the OE baffling if you want to catch those oil vapors that otherwise get by even an OE baffled/cylconic separated VC. The thought is that a NON-OE, non-baffled, and non-cyclonic separated VC (like those in the N54 aftermarket) will cause much more collection in the same environment.

Thanks,
Rob

Like this http://www.radiumauto.com/Universal-Air-Oil-Separator-Return-AOS-R-P890.aspx

 

[The Convert]

A baffle under the ports would be a good thing, but would only be necessary if the cams on the N54 sling oil towards them. Baffles on valve covers are not to prevent oil mist/vapor from leaving through the pcv valve. The baffles are only there to prevent liquid oil from being slung out.

 

[fmorelli]

You reading my mind. I was about to ask if anyone has thought about doing some baffling on the inside. That's gone on with valve covers since the beginning of time. How about a high temp 3D printed cyclonic insert .

Filippo

 

[MDORPHN]

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

Any further thoughts about this? I considering purchasing the valve cover, but am concerned about how frequently the high and low side oil catch cans will fill up.

Neil

 

[Chris@VargasTurboTech]

Any further thoughts about this? I considering purchasing the valve cover, but am concerned about how frequently the high and low side oil catch cans will fill up.

Neil

Neil, we have run ours for quite a long time on all shop cars. We have collected almost zero oil in the can over all this time, we mostly get moisture collecting I'm there from cold starts, etc.

Chris

 

[Rob@RBTurbo]

Any further thoughts about this? I considering purchasing the valve cover, but am concerned about how frequently the high and low side oil catch cans will fill up.

Neil

Most prudent thing to do would be to get some trustworthy 3rd party reviews IMO.

Rob

 

[Chris@VargasTurboTech]

Most prudent thing to do would be to get some trustworthy 3rd party reviews IMO.

Rob

Agreed, we have sold a ton of valve covers, and catch can setups. Anyone who has them feel free to speak up about oil collection in the cans.

Chris

 

[luplup]

Agreed, we have sold a ton of valve covers, and catch can setups. Anyone who has them feel free to speak up about oil collection in the cans.

Chris

Anyone able to offer any reviews on this? I'm trying to make the decision of replacing old vc with new stock vc or changing to aftermarket aluminum one by weighing the pros and cons. Thanks in advance for any input.