Big turbos and A/O separators

Discussion in 'Modifications & DIY how-to' started by Cool_____, Dec 20, 2009.

  1. goixiz

    goixiz Active Member

    ^ not bad
    just make sure you cap the inlet to the turbo

    cars with SD run it like that all the time
     
  2. Cool_____

    Cool_____ Banned

    Thanks. Contrary to what you may think I'm not against everything you say......I've already tried and done everything that you suggested with no luck. I really think a lot of the problem is the turbo is sucking in so much vac that the AOS can't do it's job.

    I'd still like that bigger drain valve if you don't mind sending it to me. That'll keep it from clogging so easily. Summer isn't an issue but this cold and high humidity is wrecking havoc via condensation.
     
  3. 07Ltd#767

    07Ltd#767 The Neighborhood Drunk

    I'm w/ you, Delette, I did the exact same thing on my car a couple weeks ago. Mine's not a sludge problem, it's a crank case pressure issue. I'm going to try and modify my AOS into a glorified catch can...either that, or see if I can't sell it. Damn you braided lines and AN fittings...

    I think this AOS would work really well on a 2.0wrx w/ a stock turbo. From what I've read / heard / discussed, anything more on a subaru is just not cutting it.
     
  4. ballistic

    ballistic Member

    is there not some kind of vacuum pump you can run?
     
  5. nicad

    nicad Yes I am a troll


    there is ;)
     
  6. Cool_____

    Cool_____ Banned

    Hey Justin you know where a good vac pump can be had without breaking the bank?
     
  7. integroid

    integroid Supporting Member

    Harbor Freight?
     
  8. Cool_____

    Cool_____ Banned

    double post.
     
  9. Cool_____

    Cool_____ Banned

    Some very good reading......

    The purpose of the stock PCV system falls under 3 categories:

    1) Performance
    2) Emissions standards
    3) Reliability

    Performance
    It is well known that performance gains can be had if the crankcase is under a slight source of vacuum which helps reduce crankcase windage losses. Many domestic users have seen decent gains by using either an electric or mechanical pump to help evacuate the pressure generated in the crankcase and even generate a vacuum present. Regaining lost power through the introduction of vacuum pressure evacuating the crankcase will not be as noticeable on a small displacement 4 cylinder as compared to a larger displacement 8cyl domestic. Despite this, it should still be of importance to explore the various configurations and attempt to "free-up" any power hidden in our engines which can easily be tested on a dyno.

    Emissions Standards and Reliability
    In order to comply with US emission standards honda had to use a closed PCV system which eliminated oil vapor from escaping into the atmosphere either from the valve cover or the crankcase breather. Oil vapors being introduced into our cylinders hurts performance and increases the probability of detonation occurring. The stock PCV system allows for the introduction of oil vapors into our intake manifold which hurts performance and reliability(a stock intake manifold is usually caked with collected oil and soot over the years).

    A stock PCV system is far from an optimal configuration in terms of performance and reliability. The best arrangement is to create a vacuum inside the crankcase of 14-15 inches/Hg (7psi). You do not want to create higher vacuum than 15 in/Hg because you will begin to suck oil from valve guides, piston rings, and bearings which will have dramatic consequences. Inducing a vacuum in your crankcase will lower oil pressure slightly which may be alarming but shouldn't be because the oil volume is still present. 2-5 % increase in whp is not uncommon with a properly setup vacuum drawn crankcase pulling 15in/Hg.

    This Vacuum will quickly remove unburnt Air/Fuel from blow-by gasses. Blow-by contaminates engine oil, contributes to sludge buildup, and causes corrosion. Turbocharged and Supercharged cars have significant amounts of blow-by because of the pressure created inside the cylinders. Your first priority should be to attempt to create a vacuum in the crankcase to remove the blow-by or at minimum make it as easy as possible for this pressure to escape.

    Evacuating the crankcase pressure can be done directly from the block or valve cover. It doesn't matter which method you prefer.

    Test Engine:

    B18c1
    /// Freshly built Engine- leak-down #s 2-3% across the board
    -- 9-1 CP pistons/Eagle Rods/Victor X Intake manifold/Lovefab sidewinder/
    Arp Head-studs
    -- 3" Down-pipe/3" Moroso Spiralflow resonator/3" mandrel exhaust/open
    dump-tube/ Tial 40mm waste-gate
    -- Freshly Built Head/ Supertech valves/ Titanium retainers/Dual Valve springs
    -- Fresh Garrett 4 bolt t3/t4 turbo// 0.60 AR Compressor/ 0.63 Turbine
    housing
    -- Custom 2.5" intercooler pipe/ Custom Spearco 3.5"X12"X20" intercooler
    -- Tuned with Hondata

    Test Equipment:

    Calibrated Dewyer Magnehelic Pressure Gauge
    0-5 psi range // Accuracy +-2% ///


    -----------------------------------------------------------------------------------
    Open Breather Ventilation
    -----------------------------------------------------------------------------------

    This method is adequate for ventilating crankcase gasses in turbocharged/supercharged cars because the extra blow-by will force its way through any filter quite easily. You want to make sure you provide as many sources as possible to allow the pressure to escape with ease.

    For H, F, and D series engines you can use the stock PCV line(excluding the PCV valve), Breather Line, and tap an extra 1-2 ports in the valve cover if wanted. You can attach a filter directly to the line or connect them to 1or2 catchcans with a breather filter on top.

    You want to place the catchcan in the highest possible location you can locate in your engine bay. This will allow the catchcan to collect blow-by gasses without consuming excessive oil and allow a drainback line to easily flow oil/gas mixture back into the engine(if you choose to use this feature).

    The sole purpose of a catchcan in an open breather system is to "trap" oil and blow-by gasses so they do not contaminate your engine bay and the environment. The surface area in the lines and the catchcan facilitate this. Increasing the surface area by using steel wool or other means will certainly help capturing these gasses but will also restrict them from escaping. The best compromise is to use a baffled catchcan such as one Moroso manufactures.



    On B series engines it is preferable to ventilate the crankcase gases through 2 ports located on the back of the block. This arrangement can be accomplished by removing the PCV chamber behind the Intake manifold bracket and sealing the stock Crankcase ventilation hole. If you are running the stock Intake manifold you will want to also plug the PCV port on the Intake Manifold as well.



    The Crankcase ventilation hole can be sealed with one of these 3 methods:
    1) Aluminum Freeze Plug (34.4mm-34.6mm)
    2) Aluminum circular plate epoxied with Devcon Liquid Aluminum
    http://www.devcon.com/devconfa...id=34
    3) http://www.z10eng.com/ makes a plug.

    It is important that you seal this opening with an Aluminum plug and not a rubber one!

    Remove the ports with a 14mm Allen(Snap-on) and install these 2 washers and ports as shown below(Honda part numbers shown):



    Use reinforced high temp hose 5/8" ID. Their will be a port on the top of your block which normally connects a line to your PVC chamber. You can either seal this or T it off one of your ventilation lines. The last thing to do is place a small filter on your breather port located on your valve cover.

    I ran this above setup for approximately 1 year with no problems. My car was daily driven hard boosting 17-18 psi. I tested this setup using the following configurations:
    1) Drain-back feature to the one of the original lines
    2) Back to the oil pan
    3) Without the drainback feature.

    When I removed the drainback feature I would fill the catchcan half full every 2-3 weeks. The evacuation lines would dis-color but never suck oil even when I used the stock Honda fittings without an anti-siphon tube. The contents of fluid collected inside the catchcan was mostly unburnt fuel and contaminants with very little oil. If you are experiencing excessive oil consumption in the catchcan I suggest you place your catchcan higher or do a leak-down test.

    I suggest manually draining the catchcan instead of using the drainback feature to eliminate gasoline and contaminants from re-introducing themselves to your oil.

    Bottom Line

    Cost: 20-150 dollars(dependent upon open filter lines or use of catchcan)
    Performance: Good(as long as their is enough ventilation)
    Reliability: Good.
    Environment: Horrible(no catchcan)- poor(Catchcan)

    -----------------------------------------------------------------------------------------
    Intake Manifold Vacuum Assisted Ventilation
    ----------------------------------------------------------------------------------------

    In Turbocharged vehicles the Intake manifold sees both vacuum and boost pressure unlike in naturally aspirated cars. The PCV valve acts as a check valve blocking any pressure in the rare occasion their is backfire in the Intake Manifold. I have heard that some individuals placing a check valve in-line and allowing the Intake manifold to assist in ventilating the crankcase. The check valve insures that boost pressure doesn't enter into the crankcase through this line.

    Ideally one would want to induce a gradual amount of vacuum up to 15 in/hg under full load. Connecting the evacuation line to the intake manifold would do the exact opposite of this. On a boosted vehicle the Intake Manifold will read 25in/hg at idle and 20-15in/Hg in low load conditions and quickly disappear when any moderate to high load conditions appear.

    In a stock vehicle this is acceptable because the PCV valve meters the vacuum as shown:

    Idle, Low load--- high vacuum pressures fully retract the pintle causing only a small vacuum draw on the crankcase.

    Mild load conditions--- vacuum present in the intake manifold is not as strong so the pintle sits in the middle of the pcv valve allowing more vacuum to evacuate the crankcase.

    High load + WOT conditions--- their is almost no vacuum present and the pintle is almost completely extended allowing the most amount of gasses to be drawn into the intake manifold.

    Engine backfire--- the pintle fully extends and seals to eliminate any gasses from flowing from the intake manifold to the crankcase.

    Not only are you pulling excessive vacuum at low load conditions you are contaminating the Intake charge with oil and unburnt fuel blow-by.

    I cannot recommend this setup to anyone.
     
  10. Cool_____

    Cool_____ Banned

    -----------------------------------------------------------------------------------------
    Intake slashcut evacuation
    -----------------------------------------------------------------------------------------



    Using a slashcut tube to create vacuum is an old trick which works on the Bernoulli effect as air rushes past the tube at high velocities. Make sure you place the slash-cut opening in the opposite direction of the airflow.

    One method for evacuating the crankcase is to allow the Intake(pre-turbo) to draw out these gasses. In my tests their was a linear load dependent vacuum drawn using this method. None to insignificant amount of vacuum drawn at idle and low load conditions, moderate load created 0.25 psi(0.5") of vacuum, and high load/WOT created a maximum vacuum of 0.5 psi (1") vacuum. One does not need to use a check valve with this approach as their is never any reason for pressure to force its way into the crankcase.

    Their is a positive and negative aspect to this approach. The great thing about this method is that it is the only method which allows one to completely eliminate any blow-by gasses from contaminating the environment. The downside is that it contaminates the Intake charge with oil/fuel/contaminants.

    Judging from the amount of contaminants I collected in my open breather catchcan every 2-3 weeks it would be absolutely insane to use this method without a sealed(no open breather element) and baffled catchcan in-line between the crankcase /valve cover and the intake. Keep in mind that most of the contaminants will be sucked into the intake as opposed to only some contaminants trapped in an open breather catchcan while the rest pollutes the environment.

    Some good news is that the Intercooler piping and intercooler will act as a very large catchcan and trap most of these contaminants before they reach the engine. The bad news is that I suggest you periodically clean the inside of your intercooler and intercooler pipe.

    Bottom Line


    Cost: 20-150 dollars(dependent use of catchcan and welding)
    Performance: Good(as long as the compressor housing/Intercooler are cleaned
    periodically and a catchcan is used)
    Reliability: Good.
    Environment: Excellent(provided that you use no other open breather elements)

    -----------------------------------------------------------------------------------------
    Mechanical Vacuum
    -----------------------------------------------------------------------------------------

    The only people right now that make this for Hondas is:
    http://www.z10eng.com/.

    The great news is that this is the best setup from a performance/reliability perspective bar-none. The bad news is that it is extremely expensive and you have to run their complete oil pump setup thus loosing your AC compressor. My conversation with one of the owners a while ago led me to believe these guys are extremely knowledgeable and will customize your complete setup specifically to your needs. You can choose between a dry sump, wet sump oil system, or even add on a mechanical fuel pump. The vacuum generator can be manually adjusted for desired amount.

    Expect to free up more whp then the standard 2-5% because this setup goes way beyond simply inducing vacuum in the crankcase.


    Bottom Line


    Cost: Variable. Expect around 2 grand.
    Performance: Excellent.
    Reliability: Excellent.
    Environment: Poor.


    -----------------------------------------------------------------------------------------
    Electric Vacuum pump
    -----------------------------------------------------------------------------------------

    I have studied and tested the idea of using old electric brake booster vacuum pumps which were made for old GM vehicles to induce vacuum in the crankcase. Using an off the shelf electric vacuum pump to draw a specific amount of vacuum is tangled with complex problems.

    These pumps run 16in/hg of vacuum at 13.7 volts and 19in/hg at 16 volts. Remember you don't want to draw more than 14-15" of vacuum and it is preferable that the vacuum is gradually increased in a linear fashion with load which these will not do without some tricky electronics.

    I have studied both mechanical and electronic approaches to solving these dilemmas to no satisfaction. After all the problems I had wrestling electrical gremlins in an electric water pump I simply don't trust my engine on this device. Another cause of concern I have is when my alternator failed while I was driving I recorded very unusual voltage numbers jumping from 10-16.8 volts in odd patterns which could case problems for an electric vacuum pump.

    -----------------------------------------------------------------------------------------
    Exhaust slashcut evacuation
    -----------------------------------------------------------------------------------------

    This is based upon the same Bernoulli effect mentioned before but uses exhaust gasses to draw out crankcase gasses instead.

    Their are 2 ways of doing this:

    1) Weld a slashcut tube in your waste-gate dump-tube
    2) Weld a slashcut tube in your exhaust



    In the first test I connected my Dewyer Magnehelic Pressure Gauge to the slashcut in my wastgate to measure the vacuum draw. As expected I only saw maximum vacuum drawn when the wastgate was open after reaching my maximum boost pressure set on my boost controller. The amount of vacuum went up from 0.25psi(0.5") to 0.4(0.8") vacuum. The numbers shown here were very similar to those shown with the Intake slashcut with the exception of being present when the wastgate started to open.


    I chose to connect my valve cover breather and top port (oem- not modified plugs) on my block to the waste-gate slashcut tube. Check valves aren't really needed here but you can use one if it make you feel better.


    For my second test I welding in a slashcut tube in my downpipe(12" from turbo). At first I had problems melting my high temp tubing with the heat from the downpipe and exhaust so I soldered together some copper pipe to solve this problem. I placed a check valve in-line on the top 6 inches of hose and wrapped it in reflective heat wrap as you can see.



    At Idle the Dewyer Magnehelic Pressure Gauge showed 0.1-0.2psi of vacuum. Driving around town was more unpredictable. The gauge would oscillate between positive pressure(when i tested without the check valve) to 0.5 psi (1") to 1.1 psi ((2.2"). It rarely displayed positive pressure but I could find no simple pattern either rpm or load dependent. Typically it would bounce around 0.6psi to 1psi.



    Here is a picture of the hose connected to the valve cover port without being tested. You definitely want to run a one way check valve in-line here.

    I purchased the check valve for 1 dollar at a local junkyard. You can find the check valve in-line on the brake booster line on any honda.

    Another source for a check valves and slashcut tubes(In case you don't feel like cutting your own is Moroso:


    Bottom Line


    Cost: 20-80 dollars (dependent upon if you have it welded or not)
    Performance: Great.
    Reliability: Great.
    Environment: Poor.
     
  11. integroid

    integroid Supporting Member

    I guess mine is the worse...my AOS has a little filter on the end of it since I couldn't connect it to my intake. Maybe that is why I am making so much JDMtight POWA
     
  12. Cool_____

    Cool_____ Banned

    So you have your IXIZ routed like it supposed to be with the exception of the intake line which in turn is simply capped off with a little filter? Where does it hang? I may just do that but I run into the issue of that nasty smell.
     
  13. integroid

    integroid Supporting Member

    Yup, sure do. It hangs on the driver side next to the steering rack. The little filter is still blue like the day I purchased it from Autozone:) My car is garaged and I park in a garage at work so it is hardly ever left outside in the cold.

    When are you coming down for your tune?
     
  14. Doug@DBW Motorsports

    Doug@DBW Motorsports Active Member

    I am surprised no body is using the exhaust to pull a vaccum on the aos
     
  15. nicad

    nicad Yes I am a troll

    that wall of text coolrex pasted talks about it, a "slashcut" (the guy sounds like a newb)

    basically you're welding in an air ejector to the exhaust stream. if done correctly, it should pull a LOT of vacuum based on the ejector design. hell, I bet you could even weld in a carb venturi in there

    I'll run some numbers on the mass flow rate of the exhaust stream and see if it's really feasible. any idea what crankcase volume is?
     
  16. Cool_____

    Cool_____ Banned

    I think Mike Sargent already tried the "slashcut".

    LOL at Nicad's newb comment....it was on a Honda forum.

    Integroid I'll be in town Feb 12/13th.
     
  17. Cool_____

    Cool_____ Banned

    Have you done it yet Doug? I've noticed it seems this only happens when the car is being beat on constantly.....like on the dyno or giving a lot of joy rides. I think the IXIZ isn't draining fast enough.
     
  18. siegelracing

    siegelracing Registered Vendor<br><b><font color="#666666">bion

    You're coming back to Atlanta for a tune?

    Siegel
     
  19. Cool_____

    Cool_____ Banned

    Yes but not from you.
     
  20. WJM

    WJM Banned

    OOOOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! :eek:hnoes:
     
  21. Cool_____

    Cool_____ Banned

    No drama here please. Back to AOS.

    I've been looking at the Grimmspeed unit and I honestly don't think it'll solve anything. The surface area that 'separates' the oil is very small due to the design of the unit. It'll gum up and clog just as fast IMO even though they state it won't with a stock PCV in place.

    So is there something 'special' about the stock PCV that'll keep condensation down? I'd think not because all aluminum motor and such will condensate regardless.
     
    Last edited: Feb 2, 2010
  22. integroid

    integroid Supporting Member

    DAMN!

    Back on topic, The Grimmspeed looks nice but I personally think you will have the same problem with any AOS.
     
  23. siegelracing

    siegelracing Registered Vendor<br><b><font color="#666666">bion

    Gotcha.

    Siegel
     
  24. Doug@DBW Motorsports

    Doug@DBW Motorsports Active Member

    I have never tried it because I have always been a bit concerned that there might be to much back pressure in the exhaust itself for it to work properly. The only times I have ever seen them in use has been on open exhaust systems on race cars.

    But I have always been interested in trying it.
     
  25. Cool_____

    Cool_____ Banned

    Yeah I've always seen it in big cammed and high compression open system drag cars. They have a TON more exhaust flow than we do. I remember walking about 10 ft behind my buddies cammed LS1 RX7 at idle and it fluttered my jeans...I couldn't believe how hard the air was coming out.

    So Doug in your 'professional' opinion what you think I should do?

    1) Keep the AOS and get a better catch can inline on the vac line going into the inlet (the Kobalt air compressor isn't doing it's job well)

    2) Keep the AOS and still use the better catch can (I already ordered a Greddy style with big ports fyi) but instead of attaching the line to the intake, put a filter on it and route it under the car like Integroid is doing

    3) Revert back to stock PCV

    4) Some other solution???
     
  26. Matt

    Matt Think before you post Staff Member Supporting Member

    option 5) sell the WRX and get a C5 Z06

    :)
     
  27. Cool_____

    Cool_____ Banned

    Corrected.....I wish.
     
  28. Matt

    Matt Think before you post Staff Member Supporting Member

    :rofl:

    I left it at C5 just due to the fact they are SLIGHTLY more attainable. :)
     
  29. Cool_____

    Cool_____ Banned

    Here ya go Doug.....Mike Sargent and Crawford have both tried this and got pressure instead of vac. Interesting.......how'd that happen?


     
  30. Doug@DBW Motorsports

    Doug@DBW Motorsports Active Member

    Yea... thats pretty much what I thought would happen which is why I never tried.

    Good to know though.

    As for your car, I have no idea. I run a different AOS and have no problems with it on my car.
     
  31. Cool_____

    Cool_____ Banned

    Crawford kit? If so I've read and seen proof of all them having the same issues so I dunno.

    How would the exhaust kit get pressure instead of vac? Is it due to the pulses in the exhaust?
     
  32. Doug@DBW Motorsports

    Doug@DBW Motorsports Active Member

    I have had the crawford one on both my street car and race car. I never had them push alot of oil out, at most I would see a couple table spoons after a track session.

    But on the street I can't imagine seeing a ton come out unless it was installed wrong or the motor was hurt.
     
  33. integroid

    integroid Supporting Member

    There is not enough velocity to create a vacuum or too much restriction with a muffler that creates back pressure?
     
  34. Cool_____

    Cool_____ Banned

    Well that's the funny thing. Regular driving with the occasional pull NOTHING. But on the dyno or giving joy rides beating on the car you see this. It's hard to tell how much oil vs water is there but it is very thick and gunky like it's more water than oil. I think the major issue is condensation and it's stopping up the inside of the AOS. Hard to tell/know for sure.
     
  35. nicad

    nicad Yes I am a troll

    I don't think the air ejector/eductor systems they are using are designed properly. you need a convergent -> divergent nozzle to increase the speed (kinetic energy) of the exhaust. in the divergent section, this ke is converted back to flow work and a vacuum is created. you can't just stick a tube in there and expect it to work

    I know they work fine. I used them everyday on steam turbines for gland sealing steam and also for condensers. you can get down to 28"Hg this way, BUT using air is not as efficient, so you might need to run a two stage setup.
     
  36. Cool_____

    Cool_____ Banned

    Um what? LOL. Is there a kit you recommend?

    I've noticed the Mr Gasket Kit is just a tube but the Moroso one has these little holes in the tubes. Is that what you are talking about with the fancy talk Justin?
     
  37. Matt

    Matt Think before you post Staff Member Supporting Member

    I don't think there is a kit for nuclear submarines...
     
  38. Cool_____

    Cool_____ Banned

    Sure there is. You just have to go and steal it. LAWLZ.
     
  39. nicad

    nicad Yes I am a troll

    a kit? no, this would have to be machined.
    this is a pretty good diagram

    [​IMG]
     
  40. Cool_____

    Cool_____ Banned

    Justin how hard and expensive you think it would be to make this a reality in the Subaru?
     
  41. nicad

    nicad Yes I am a troll

    dunno. call forged, they might be able to help
     
  42. Cool_____

    Cool_____ Banned

    Lawlz. Then it'll truly be innovation eh?
     
  43. nicad

    nicad Yes I am a troll

    here, let me push you in the right direction

    [​IMG]
     
  44. Cool_____

    Cool_____ Banned

    Vac pump?
     
  45. nicad

    nicad Yes I am a troll

    yes.
     
  46. Mike@TTR

    Mike@TTR Active Member

    The one we are using works just fine on larger v8 motors that are NA or supercharged. It might STILL work fine on the subby, but the position it is in did not work. It might be too far down the exhaust stream where it has slowed too much. Still not convinced it won't work. With a proper check valve I still think it would work ok. Ben saw at most 1-2 in hg vacuum.

    The only difference in the Moroso kit and the Mr. Gasket is the notch...it is just to aid in locating the tube to the proper depth and angle.
     
  47. Cool_____

    Cool_____ Banned

    I'm looking hard but the biggest issue is running them in oily air like the PCV system. Those pumps are not in any way designed for oily air. Lots of quick fast failures.

    If I can find an electric system that doesn't pull too much pressure then I think we are game.

    Nicad you are the math genius....how much vac you think the intake on a 35R can generate?
     
  48. nicad

    nicad Yes I am a troll

    probably 2"Hg max. I'd have to look at the compressor map, since it has pressure ratios on the Y-axis. that way you could figure out the intake pressure at a given flow rate and temperatures (assuming non choked flow conditions)
     
  49. Cool_____

    Cool_____ Banned

    Here's what I drew up. I dunno about one head port going to the AOS but I don't think both need to be closed.....there needs to be some sort of fresh air going into the system I would think. Discuss

    [​IMG]
     
  50. nicad

    nicad Yes I am a troll

    you have WRX heads don't you? so only one vent..
    if you had two vents, I'd say cap one off, and equalize the other with the crank case and plumb the CCV to the AOS.

    this is of course assuming an AOS actually "separates" anything like it should, which I'm not really convinced they do.
     

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