Adjustable PCV valve

Mopar Performance Issues

  1. 66Valiant528

    66Valiant528 Well-Known Member

    Messages:
    353
    Likes Received:
    220
    Joined:
    Aug 20, 2019
    Location:
    Medway Ma
    Local Time:
    10:34 AM
    I haven't been running a pcv valve on my street dual quad 440 because I don't want to suck oil into the intake. I've considered a catch can and a pcv valve. But I know different valves function differently and your best guess is to find the pcv that was used from the factory with a similar cam/set up. Great except most pcv are now 1 size fits all. Before I jump into a 130 dollar adjustable one I was looking for suggestions. What are you running for a set up? Screenshot_20220424-201150_Chrome.jpg
     
  2. Rat Bastid

    Rat Bastid Dunamis Metron

    Messages:
    1,793
    Likes Received:
    1690
    Joined:
    Nov 23, 2020
    Location:
    22 The Avenue
    Local Time:
    7:34 AM
    Do it. Make sure the PCV valve is baffled and use a catch can.
     
    • Agree Agree x 2
    • 416stroker

      416stroker Well-Known Member

      Messages:
      818
      Likes Received:
      77
      Joined:
      May 14, 2006
      Location:
      Kalamazoo, Mi
      Local Time:
      9:34 AM
      PM sent
       
    • AJ/FormS

      AJ/FormS 68 Formua-S fastback clone 367/A833/GVod/3.55s FABO Gold Member

      Messages:
      22,801
      Likes Received:
      9829
      Joined:
      Jan 19, 2014
      Location:
      South-Central Manitoba,Canada, 900ftelevation
      Local Time:
      9:34 AM
      If your engine is making that much blow-by as to concern you about sucking oil into the intake, wouldn't it concern you more about the blow-by in the first place?
      Remember, at WOT, the PCV goes to minimum flow, the breather vents the CC gasses to the atmosphere, and the whole thing wants to run backwards. This doesn't happen only at WOT either, but at anytime the pressure in the CC exceeds the flow capability of the PCV.
      Lets say you are just speeding up normally at PT and a vacuum of 8 inches, and say over 2400rpm . In this condition; If the engine is making more blow-by pressure than what the PCV is designed to deal with, then the excess will depart the CC thru the breather.
      So yeah, at high manifold vacuum the PCV is running wide open, trying to create a vacuum in the CC. But as soon as the vacuum drops, the spring-loaded pintle inside the PCV, due to loss of vacuum, also drops; back to it's calibrated minimum flow. This protects your engine from excessive ingestion of oil-laden blow-by gasses.
       
    • 66Valiant528

      66Valiant528 Well-Known Member

      Messages:
      353
      Likes Received:
      220
      Joined:
      Aug 20, 2019
      Location:
      Medway Ma
      Local Time:
      10:34 AM
      I have no blow by. I just haven't been running a pcv . I've seen intakes with ports for the pcv and some have been discolored with oil residue. I understand how a pcv system works and understand that my chain store pcv is probably not right for my engine combination. Just wondering who has done what. I like the idea of a fixed system as I see the adjustable one can be set up for if that's what your combination needs. Thanks for the input.
       
    • AJ/FormS

      AJ/FormS 68 Formua-S fastback clone 367/A833/GVod/3.55s FABO Gold Member

      Messages:
      22,801
      Likes Received:
      9829
      Joined:
      Jan 19, 2014
      Location:
      South-Central Manitoba,Canada, 900ftelevation
      Local Time:
      9:34 AM
      The PCV has to be connected to the proper port on the front of the carb, just below the butterflies; so IDK what you have been seeing.
      If your engine has no blow-by, then just hook up any old PCV that fits and routs easily. This is not rocket science. Your carb will need readjusting. Just make sure you start with a properly adjusted transfer-slot exposure, and modest idle-timing.
      As mentioned ; make sure your valve covers are properly and adequately baffled, and every thing will be fine.Don't forget the breather has to work in BOTH directions.
       
    • 66Valiant528

      66Valiant528 Well-Known Member

      Messages:
      353
      Likes Received:
      220
      Joined:
      Aug 20, 2019
      Location:
      Medway Ma
      Local Time:
      10:34 AM
      The M/P covers are baffled. I have 14 inches at hot idle and like 20 cruising. It's pretty amazing considering it's a 520/540 282S solid cam with dual 450s. I hooked up a generic parts store one because those numbers are pretty "stock"and yes I need to jet up a little according to my O2 sensor. Again just wondering what people have been doing with there pcv systems and input on the adjustable one.
       
      • Thanks! Thanks! x 1
      • mderoy340

        mderoy340 Well-Known Member

        Messages:
        2,524
        Likes Received:
        1338
        Joined:
        Aug 2, 2012
        Location:
        Melbourne FL
        Local Time:
        10:34 AM
        I run a wagner adj and a $25 amazon catch can. Zero oil suck in the carb. It takes a little while for the old TRW forged slugs I run to expand and this setup works for me.
         
        • Agree Agree x 2
        • Like Like x 1
        • Bewy

          Bewy Well-Known Member

          Messages:
          2,084
          Likes Received:
          1358
          Joined:
          Jan 1, 2021
          Location:
          Australia
          Local Time:
          12:34 AM
          At idle, your average PCV pintle valve opening is equivalent to about a 7/64" hole. So what I have been doing for a loooong time is cutting open factory PCVs, gutting them, & brazing in a steel disc. In which I drill a 7/64" hole.....
          Now have a working PCV at idle & not dependent on idle vacuum for reliable operation.
           
          • Agree Agree x 1
          • 66Valiant528

            66Valiant528 Well-Known Member

            Messages:
            353
            Likes Received:
            220
            Joined:
            Aug 20, 2019
            Location:
            Medway Ma
            Local Time:
            10:34 AM
            Interesting. Kind of like the shut off vavle idea. Fixed orifice.
             
          • Brooks James

            Brooks James VET, CPT, Huey Medevac Pilot FABO Gold Member

            Messages:
            2,647
            Likes Received:
            1438
            Joined:
            Dec 12, 2020
            Location:
            Fruitland Park Fl
            Local Time:
            10:34 AM
            Put a small brass valve in the line, adjust as necessary
             
          • Rat Bastid

            Rat Bastid Dunamis Metron

            Messages:
            1,793
            Likes Received:
            1690
            Joined:
            Nov 23, 2020
            Location:
            22 The Avenue
            Local Time:
            7:34 AM
            Just buy the Wagner and don’t look back. Any fixed orifice PCV is limited at best. You can drill holes, put brass in line and dick around and it’s still not adjustable.

            I have now used a dozen of them. They all have been different engines with different levels of performance. Not once has one not been far better than the junk they took off.

            The guys who are telling you to screw around with OE style stuff have either never used the Wagner valve or are too cheap to see the value of it.

            Buy it and tune it. You won’t be sorry.
             
            • Agree Agree x 3
            • weedburner

              weedburner Well-Known Member

              Messages:
              239
              Likes Received:
              261
              Joined:
              Oct 20, 2015
              Location:
              Wa State
              Local Time:
              7:34 AM
              Pretty easy to make a $6 NAPA pcv valve like this adjustable...

              pcv2f.png

              Just drill a hole in the plastic elbow and add a long screw to hold the pintle off the low flow position. Here's an exploded view of what's inside the above valve...

              evacpcv3.jpg

              Here's where to add the screw...

              evacpcv5.jpg

              Here's the view of the screw from inside the valve...

              evacpcv4.jpg

              I pulled the plastic elbow off the above valve and installed it on a valve that had not been cut apart. Been using the same modified valve since May of 2013 with no issues, it draws 15"Hg of vacuum in a sealed crankcase @ 2500rpm cruise. I run 12lb oil rings on the street with 5W-20 Mobil1, without crankcase vacuum it went thru a qt in about 250mi. After sealing up the crankcase and adding the modified pcv valve, I might add 1 or 2 qts all summer. Lack of oil leaks is a huge upside as well.

              Grant
               
              • Like Like x 3
              • Thanks! Thanks! x 1
              • 66Valiant528

                66Valiant528 Well-Known Member

                Messages:
                353
                Likes Received:
                220
                Joined:
                Aug 20, 2019
                Location:
                Medway Ma
                Local Time:
                10:34 AM
                Impressive!
                 
              • oldkimmer

                oldkimmer FABO Gold Member FABO Gold Member

                Messages:
                21,862
                Likes Received:
                8657
                Joined:
                Nov 11, 2006
                Location:
                Kindersley, Saskatchewan,
                Local Time:
                9:34 AM
                Ingenious idea I say. Kim
                 
              1. This site uses cookies to help personalize content, tailor your experience and to keep you logged in if you register.
                By continuing to use this site, you are consenting to our use of cookies.