I am trying to do my research and learn from the wisdom of others before I finalize the plans for my crankcase ventilation / catch-can system.

Background: The car has 21,500 miles on it, and has been running with a freshly built 2.3L engine built by buschur at 20,000 miles in 2014. I did not realize a catch-can was necessary with a built motor, and Buschur did not suggest it so I did not have it installed as a "supporting mod". I also have a HTA3076R ETS turbo setup. As I've learned more over the years, I believe I have some oil leak issues that are being caused by the build up in pressure in the crank-case due to the built motor and bigger turbo. PCV system is completely stock, and Buschur simply put a "sping" to hold down the dipstick tube. Oil is barely leaking by what looks to be the turbo-oil return tube, and possibly by the front main seal. (I run brad penn 20-50)

I had originally thought of purchasing my catch-cans from STM, but now I am interested in going with saikoumichi (far better customer service)

Can I please borrow the experience of the community to review my thoughts on this project and give suggestions? I did read every post of the 110-page "crankcase ventilation issues" thread (it took me 16 hours). I am trying to finalize my plans, and my shopping list before committing

 

bump- does anyone with experience have any thoughts? I really want to get to ordering parts.

 

im not sure how much power you plan to push (or boost), but just in general... .. not many high hp set ups will pull vacuum on the oil catch cans.

there is just to much air movement and you will pull oil vapor back into the intake (in your setup... on both sides)
which ends up putting oil in the turbo and in the intake... makeing a mess


most just vent the catch cans to atmosphere.

and.... if you vent to atmosphere, no reason for the PCV

and the crank case vent is really not needed if you do the valve cover vents correctly...

 

This is exactly the setup I plan to use on my new built.
On my current engine (stockish Evo 6), I simply use 2 saikou michi OCC in the oem system. Works perfectly, I truly believe this « closed » system is perfect, especially for a street car.

My 2 cents : for the « rear » system, I plan to use radium PCV valve ( http://www.radiumauto.com/10AN-ORB-P...ves-P1155.aspx ) and put it between OCC and intake manifold. (Currently I use the stock system, but it « pressurize » the OCC under boost. No issue since 10 years but I don’t like it).
I will re use my 2 saikou OCC for the two lines coming for the block (the stm fitting is a metric to 6AN fitting) and the front / right valve cover port.
I just bought one 10 AN and one 6 AN union fittings and will machine them to directly fit them in the valve cover.

 

Interesting- so you suggest putting the PCV between the catch can and the intake manifold, as opposed to the valve cover and catch can. I see how this would prevent the catch can from being pressurized with boost.

 

Exactly.
As I said I’ve been running since years with the OCC in the stock system (with stock engine, running around 20 psi max) with no problems.
but I will do as I said on my second engine, so boost pressure will be kept in the IM.

 

Before you modify your valve cover let me know. If your VC is 100% stock I’ll trade mine for yours... my VC had the factory breather port on the left side opened up for a larger breather tube and is tapped for threads and I’ve since removed that system and want it back to 100% stock. Other than that my VC is factory and in flawless condition. Let me know if you’re interested in a swap.

 

As someone thats installed the STM V2 catch can recently, I cant say I'd recommend the balance shaft inspection port line because its filling my can with good oil. After about a 50 mile cruise with some pulls in there, I drained just about a cup of good oil from the catch can.

 

You should not need any more venting than just using the two factory ports on the valve cover, which are baffled. You can convert the rear port to a true -10an fitting and that should be sufficient to evacuate block pressure. You can then use the front port for the intake manifold PCV if you choose.

 

with the rear port where the factory PCV is.... the limiting factor that I see is the size of the PCV valve itself right?

 

The stock PCV valve on the rear of the valve cover is not limiting because it only draws on the block during off-boost driving, which is when potential block pressure is minimal. Remove the PCV valve from the back of the valve cover and then remove the grommet from that hole and purchase a press-in -10an fitting (link below). At this point the -10an fitting will be used for block PCV during on-boost driving.
http://www.radiumauto.com/10AN-Male-...d-In-P940.aspx

You can then use the smaller front port on the side of the valve cover for your intake manifold PCV (off-boost driving). You can reuse the stock PCV valve somehow, like I did, or you can purchase a one way valve to place in between the intake manifold and the front port, but preferably with a can in between.

 

I bought Kracka's crankcase valves a long *** time ago and never used em. The PCV setup debate has always been a confusing read so I understand where you're coming from with the long reads.

 

What is the thread size on the OEM PCV valve as shown below?

 

To use it I purchased a -10an cap and then drilled & tapped the end 1/8" NPT and screwed in the valve. I advise that you angle the valve down (hose barb side down) so the sliding plug stays in the open position until it is pushed into the closed position by boost pressure. If you have the valve level with the ground the internal spring does push the plug far enough open and it gets stuck in a partially open/closed position. You can see in the second pic I initially had it level, but then purchased a 90deg adapter so I could angle the valve down about 45 degrees.

 

240Z - Thank you for spending so much time replying with all of those details! I feel kind of dumb, but I think I realize what you were trying to teach me now.

Before I clarify my understanding let me start with a quick description of how the original OEM pcv setup works under easy cruising (manifold vacuum)

1. Fresh air enters the intake through the filter.
2. Some of it goes through the turbo, and some gets sucked into the small opening in the valve cover near the transmission side/drivers side.
3. This air gets sucked through the crankcase, and then travels through the block where it mixes with the nasty crankcase vapors.
4. It exits the block in the back near the passenger side hole in the back of the valve cover.
5. It goes through the PCV valve and eventually makes it into the intake manifold.
6. At this point it gets burned through the cylinders.

So- in order to not have to remove the valve cover and modify it, you are actually REVERSING the flow direction here.

1. Fresh air enters the air filter
2. You removed the grommets and make your REAR hole bigger- so this air goes all the way around the back side of the engine and enters the BIG hole in the valve cover through a large 5/8" hose where the PCV valve USED TO GO.
3. It mixes with crankcase vapors.
4. It exits the valve cover/block through the LITTLE hole near the driver side/transmission.
5. It goes through a longer hose and through the PCV valve which you relocated.
6. It makes its way back into the intake manifold and gets burned in the cylinders.

So essentially it is the same style function as factory, just you are taking advantage of the ability of the rear hole to be easily enlarged where you can make it bigger without the need to remove the valve cover, drill any magnesium or remove baffles.

Instead of traveling "NORTHWEST" inside the crankcase the travel path in your engine is "SOUTHEAST"

Please verify that I understand this correct. If I am correct I want to say this:

I thought about your approach for 2 full days. I do feel dumb for not seeing this originally. I do see the elegance of it.

The thing that I don't like is that it seems like there will be a need for longer hoses. My engine bay is very busy already and I hate to make it even busier. It would be nice however to not need to remove the valve cover and play with the baffles/drilling and such.

The thing I like about my original plan is that I can keep the large port near the intake side of the engine, so I can easily mount my can and keep my hoses short.

I have since thought about it and I DO NOT think I will use the inspection hole in the block for the balance shafts, since it seems this creates a lot of oil making it into the can.

Now that I (hopefully) understand your setup let me ask you this. If I use the driver/side transmission side port of the valve cover for my vent *by enlarging it*, is it silly to do any modifications to the back port where the PCV is? In other words- since the PCV should be CLOSED during boost- why not just keep the back side of the valve cover stock, and only insert the catch can between the oem PCV and the intake manifold.

Thank you once again for your attention to this thread and I appreciate the knowledge you've shared with me!!!