Don't forget @Jason@Propulsive-Dynamics who did the actual testing where a lot of this data came from originally.
RB external PCV setup
- Thread starter TurboMike
- Start date
Don't forget @Jason@Propulsive-Dynamics who did the actual testing where a lot of this data came from originally.
That is the problem when you start to name names ... you always leave people out that should be recognized. The people that I listed were the people that I had access to pester for information and took the time to directly answer my questions, and give recommendations, even though I had not purchased anything from them at the time. Sorry to everyone that I omitted, but thanks for sharing the information.
Really really nice explanation. Thank you!!
I thought the BMS catch can usually gets installed without the flapper valve, but i just searched the install guide and saw that they reuse it.
I think i am running an VTA hose without the flapper iirc- i think i will change it, because with a setup like this there is no vacuum in the crankcase.
VTA being illegal isn´t a topic here in germany- i am not allowed to drive my car with all the mods anyway. Really crazy here.
What i really would like to know is if the low load Side was designed the way it is because of a healthy engine or because of emissions and stuff. If it would only be emissions, VTA without the flapper (setup i have now) is not the worst idea, cause there is no vacuum on the crankcase and the PCV only "pulls" on the VTA hose, so that my intakes should stay cleaner.
Does anybody know how other engines handling the PCV System?
I thought the BMS catch can usually gets installed without the flapper valve, but i just searched the install guide and saw that they reuse it.
I think i am running an VTA hose without the flapper iirc- i think i will change it, because with a setup like this there is no vacuum in the crankcase.
VTA being illegal isn´t a topic here in germany- i am not allowed to drive my car with all the mods anyway. Really crazy here.
What i really would like to know is if the low load Side was designed the way it is because of a healthy engine or because of emissions and stuff. If it would only be emissions, VTA without the flapper (setup i have now) is not the worst idea, cause there is no vacuum on the crankcase and the PCV only "pulls" on the VTA hose, so that my intakes should stay cleaner.
Does anybody know how other engines handling the PCV System?
The problem comes as a result of the turbos, naturally aspirated engines always have "some" vacuum available to the PCV system, even if it is minimal at wide open throttle.
What I wish is that BMW had come up with a better design of oil separator to return the oil mist to the crankcase. My low side OCC catches a lot of oil and I have to drain it often. Because of how tight the engine compartment is, it is not a easy process to drain, particularly if the engine is hot.
What I wish is that BMW had come up with a better design of oil separator to return the oil mist to the crankcase. My low side OCC catches a lot of oil and I have to drain it often. Because of how tight the engine compartment is, it is not a easy process to drain, particularly if the engine is hot.
I have to drain mine often as well. Every 200 miles it fills up to the top.i was thinking of attcahing a valve on the bottom for easy draining.
Mine is not that bad, but it certainly catches a lot.
Is what your can collects clean oil, or is it the milky water-oil mixture?
Is what your can collects clean oil, or is it the milky water-oil mixture?
Its the milky yellow stinky shit, I actually have failed rings and am bypassing exhaust into the valve cover, so ive had a ton of moisture in my crank case. But even with blow by im burning next to no oil with the new external pvc, compared to 1 quart every 300 miles
It states on the RB website it will work, but wont completely externalize the pcv system, so you could potentially still have problems and valve cover leaks/cracks, if you plug them it eliminates the problem
You can use without as the valve included still does its job. However best plug up the ports as soon as you can
I have. He's reviewed the N54 engine docs that were released back in 07 & some other "typical" routing pics I sent. His can is different than most & has valves built into it similar to how we have the flapper & pcv. This allows him to configure both hi/lo or clean/dirty hoses to the same can. However, his beliefs on crank case pressure is different than others on this platform...
http://www.mightymousesolutions.com/single-post/2016/02/02/Crankcase-vacuum-at-wide-open
Popular subject going on a couple message boards; there is an idea boosted by the 'copy a racecar' type that maintaining some high level of crank vacuum is 'better'. Is it really? My thoughts:
The best way to avoid cank pressure IMO is to just 'let it go' instead of re-route. This applies for any dual purpose build.
When you re-route blowby to a suction source in order to not only accept this volume, but overcome it in order to create vacuum, extra check valves and restrictions from these lines need to be considered, and the volume of fumes removed must always be regulated vs. current engine conditions hp /crankcase flow. For legit 'racecars' this means buying the right size vacuum pump, gearing it to the right speed, having the right size lines running to it, and from it, to the right sized catch can to handle the exhaust, and having a regulator for your flow range installed, and fine tuned (for a given combination in good health).
- Complex YES!, could we make some version of this using only the engine, ...sort of.. Will it REALLY work? ehh..
- interest in steady supply of crankcase vacuum is a very common one, but without a separate vacuum pump produces no real tangible performance benefit.
- Any hp increase from potential ring seal improvement is by re-routing these fumes to the air intake is immediately offset by trying to make hp off of combustion gasses vs. all brand new air.
- Also consider to get this strong / tangible /measurable vacuum from some port between the main engine filter and the throttle body, there must be some restriction to cause this vacuum; The same restrictions you spend hundreds on, new or larger air filters, inlet tubing, throttle bodies to REDUCE this restriction. If you have measurable vac here, it is COSTING you hp already.
-Further, putting around the street with a functional pump in action will not get you to work faster or get you better mileage, the chic ks won't dig it either, but it will accelerate ring wear. Personally my most high strung cars still spend over 90% of their time, on the street, crusing, going the speed limit-ish.
Here is a video about fine tuning PCV flow I made which considers that 90%.
https://www.youtube.com/watch?v=juH6eBoOInM
This is the concept/layout he came up with for his can on an N54 (based on what I gave him & my limited understanding). We were starting to determine "best" hose/fitting sizes based on my build, but I've held up till I get my intake manifold & determine if I want to try his approach or one that is more common. He is very helpful & appears to be very knowledgeable. I can see some merit to his points...
David said according to his understanding the orig flapper & pcv could be retained. Also, said his can only vents when there is more pressure inside than outside because of valving & it's not just a can w/ a filter.
This was his explanation:
stock operation
vacuum:
clean air in from air filter tubing at one end (regulated) dirty air out the other (regulated) to intake manfiold
boost clean air side now becomes the crankcase vent (flap open) and the pcv vaccum side should be completely or at least mostly closed to protect from boost / backfire
MM canned operation
the vacuum side flap and orfice both jobs are handled by the pcv valve built into my can exit (always to intake manifold vacuum) with that job considered, we can vent to the can with the 3/4" hose ( i rate at 1200hp if unrestricted) from the large side of the rocker the connections at the air filter tubing and oem pcv orifice can now be joined maintain fresh air to crankcase during vacuum cycle the above changes with my pcv can now direct all vacuum fumes through the can for stock operation plus catch can for the oil, and during crank pressure the can receives the flow instead of the air filter tube, less blowby air to the air filter means more power, and the catch can of course catches any oil heading to atmosphere
the restricted orifice between the air filter tube and the other end of the rocker cover still allows fresh air circulation to the crankcase (no vacuum lock) but nicely baffled to reduce any oil splash, or suction from a highly restricted/ clogged / undersized air filter we can further improve any of this by manually adding another fitting from the rocker cover to the can for more vent capability, no other changes
David said according to his understanding the orig flapper & pcv could be retained. Also, said his can only vents when there is more pressure inside than outside because of valving & it's not just a can w/ a filter.
This was his explanation:
stock operation
vacuum:
clean air in from air filter tubing at one end (regulated) dirty air out the other (regulated) to intake manfiold
boost clean air side now becomes the crankcase vent (flap open) and the pcv vaccum side should be completely or at least mostly closed to protect from boost / backfire
MM canned operation
the vacuum side flap and orfice both jobs are handled by the pcv valve built into my can exit (always to intake manifold vacuum) with that job considered, we can vent to the can with the 3/4" hose ( i rate at 1200hp if unrestricted) from the large side of the rocker the connections at the air filter tubing and oem pcv orifice can now be joined maintain fresh air to crankcase during vacuum cycle the above changes with my pcv can now direct all vacuum fumes through the can for stock operation plus catch can for the oil, and during crank pressure the can receives the flow instead of the air filter tube, less blowby air to the air filter means more power, and the catch can of course catches any oil heading to atmosphere
the restricted orifice between the air filter tube and the other end of the rocker cover still allows fresh air circulation to the crankcase (no vacuum lock) but nicely baffled to reduce any oil splash, or suction from a highly restricted/ clogged / undersized air filter we can further improve any of this by manually adding another fitting from the rocker cover to the can for more vent capability, no other changes
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In other platforms that I am heavily in, we remove PCV all together and just vent the block via catch can that is open to atmosphere. Helps a great deal with blowby. No vac pump needed. Has anyone tried this method on N54? You see this method used on a lot of platforms where the catch can is fed directly with the valve cover or block.
I just ordered RB's external PCV kit and installed it (took a total of 20min). I haven't done anything to the high side, but am wondering why nobody has done a simple 12v electric vacuum pump on the high side to provide vacuum during high load/boost. Run the vacuum pump through a catch can of its own so you don't kill the pump with oil blockage. And possibly have a hobbs switch turn the pump on/off. Other than the complexity, the cost is minimal...these pumps are a dime a dozen and can be had new for around $20.
A few have done exactly that. Installed a vacuum pump, triggered by a pressure switch, pulling through a catch can. There are images of the install somewhere.
The only part I did not care for was that he placed the pump under the car, near the passenger footwell. Made the tubing and wiring pretty long, but we are pretty limited in available space to put it elsewhere.
The only part I did not care for was that he placed the pump under the car, near the passenger footwell. Made the tubing and wiring pretty long, but we are pretty limited in available space to put it elsewhere.
