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Crankcase Ventilation

Discussion in 'The Hokey Ass Message Board' started by choppermatt, Mar 12, 2009.

  1. choppermatt
    Joined: Dec 1, 2004
    Posts: 303

    choppermatt
    Member

    Im building a SBC from the ground up. Its got almost everything new inside, but I've realized I have a problem. I'm using an old Edelbrock intake manifold with an oil fill tube in the front. I have cal-custom finned valve covers with no holes for vents or PCV valve. I'm using a block from 1970 that has no provision for a draft tube. What can i do to have enough crankcase ventialtion without sacraficing the looks of an older small block? I've seen in small books the idea of a vent in the oil pan? Or maybe hiding a PCV valve?
     
  2. spinout
    Joined: Jan 15, 2008
    Posts: 333

    spinout
    Member
    from Dallas, TX

    You could run an electric fuel pump, and use the old fuel pump hole. You can hollow it out and get big air flow into and out of the crankcase. I've seen this done, usually with a hose or pipe going up from the hole.
     
  3. Shifty Shifterton
    Joined: Oct 1, 2006
    Posts: 4,964

    Shifty Shifterton
    Member

    Do a search on PCV and you'll find a handful of good writeups on where to hide it.
     
  4. WildWilly68
    Joined: Feb 1, 2002
    Posts: 1,724

    WildWilly68
    Member

    You can drill the intake for one behind the carb. Edelbrock makes one with the oil fill tube and the hole already drilled, but I don't see why you couldn't drill it yourself. I ran this same setup for years.
     

  5. tooslow54
    Joined: May 6, 2005
    Posts: 929

    tooslow54
    Member

    Best advice. Do a search, if PCV is too short try key words like "positive" or "ventilation"...lots of threads on this.
     
  6. 53sled
    Joined: Jul 5, 2005
    Posts: 5,818

    53sled
    Member
    from KCMO

    type jalopyjournal.com and what ever you want to find into google, no limit on characters!
     
  7. hillbilly4008
    Joined: Feb 13, 2009
    Posts: 2,918

    hillbilly4008
    Member
    from Rome NY

    I gotta see a good "how to" on this one!
     
  8. bdmridgeback
    Joined: Nov 29, 2012
    Posts: 5

    bdmridgeback
    Member

    My fuel pump block off plate that I tapped and ran my pcv breather line to it for crankcase ventilation....



    [​IMG]
     
  9. andywuc
    Joined: Jul 1, 2013
    Posts: 4

    andywuc
    Member
    from london

    I ran this same setup for years.[​IMG]
     
  10. johnybsic
    Joined: Oct 8, 2009
    Posts: 612

    johnybsic
    Member
    from las vegas

    Well damned if this isn't interesting.... Hmmmmmm new one for me

     
  11. JeffB2
    Joined: Dec 18, 2006
    Posts: 8,927

    JeffB2
    Member
    from Phoenix,AZ

  12. fiftyv8
    Joined: Mar 11, 2007
    Posts: 5,211

    fiftyv8
    Member
    from CO & WA

  13. BobMcD
    Joined: Jan 25, 2013
    Posts: 322

    BobMcD
    Member

    Some of the later oil fill tubes around 68-69 had a bung welded on for a PCV valve to thread into.
     
  14. overspray
    Joined: Jan 14, 2003
    Posts: 1,232

    overspray
    Member

  15. outlaw256
    Joined: Jun 26, 2008
    Posts: 2,023

    outlaw256
    Member

    been doing this for over 40 yrs and I never have seen this!!!
     
  16. Dan Timberlake
    Joined: Apr 28, 2010
    Posts: 1,327

    Dan Timberlake
    Member

    There can be significant engine life benefits with PCV. To realize the benefits of crankcase ventilation there should be airflow from the corners or ends of the engine through the engine, just like the road draft system had.

    Providing a Vent for blowby in order to reduce crankcse pressure is only half the deal for an engine I want to run well and last thousands of miles.
    http://www.consumerreports.org/cro/2012/12/the-black-death-of-sludge/index.htm
     
  17. One of the magazines just had an article on this, should be on the stands, I forget which one. I think they drilled a hole in the side of the valve cover, though, you may not want to do that on a nice set of Cal Customs.
     
  18. Go ya one better if you want to get a little more aggresive. Use the mechanical fuel pump AS a vacuum pump. Plumb the suck side into the file tube, valve cover, or drill and tap the a hole throught the manifold into the lifter valley (Buick 400/430/455)have a PCV
    grommet this way behind the carb pad. Plumb the the out/exh side of the fuel (now vacuum pump)into a puke can/tank. I used the original Moon tank on the front of our '56 as the vent/puke tank. We have also used the mechanical fuel pump as a vacuum source for a power brake resevoir on power brake cars with big camshafts. This is the "pan evac" system on our '56. I tried to make it look like an old school fuel system at first glance. You'll notice however that the lines from the fuel block are plumbed into the bottom half of the tunnel ram where they suck "draggon breath" from the lifter valley. The Moon breathers on the valve covers are there for looks. I drilled and tapped the valve covers for 3/4 pipe plugs that are hidden by the Moon breathers. If we need additional breathing capability, I can drill the center of the pipe plugs out, or simply remove one or both of them. IMAG0287.jpg

    IMAG0295.jpg
     
  19. If you use the carb as a vacuum source, put a clear fuel filter between the carb and the pcv valve to seperate the oil from the crankcase "breath", that way the engine is not ingesting oil (or at least a whole bunch less)into the intake manifol.
     
  20. saltflats
    Joined: Aug 14, 2007
    Posts: 10,904

    saltflats
    Member
    from Missouri

    If you drill the intake behind the carb use one of the lifter vally baffles so it wont suck spashing oil from the lifter vally.
     
  21. As the fuel pump boss area can be used as I the photo, you can also use the "top" bolt on the front side of the timing chain area can also be used so that a mechanical pump can still be used. We have done both ways since the 70's, good luck.
     
  22. bdmridgeback
    Joined: Nov 29, 2012
    Posts: 5

    bdmridgeback
    Member

    Here are a couple other pics of my intake and such.

    I have a fill tube in the back of my my Scorpion intake with a breather in it. Then ran pcv off back of carb down to fuel block off plate.
     

    Attached Files:

  23. verno30
    Joined: Aug 25, 2008
    Posts: 1,087

    verno30
    ALLIANCE MEMBER

    [​IMG]

    I drill and tap a 3/8 NPT into the back of the intake and build a baffle on the underside of the intake. Then, I use a PV1045 PCV and connect it to the back of the carb.

    Used this on engines over the last 12 years with no problems
     
  24. Willy_P
    Joined: Mar 19, 2011
    Posts: 762

    Willy_P
    Member

    Subscribed.
    I have been looking for a solution to modify some corvette valve covers without hosing them up. I just stumbled on one more creative way this evening from a fellow named Van Pershing in Tucson AZ, You have to modify the valve cover, but it is very well hidden. The process is well photographed and described on thisweb page
    http://www.persh.org/pickup/ValveCovers.htm
     
  25. Willy_P
    Joined: Mar 19, 2011
    Posts: 762

    Willy_P
    Member

    Verno30,
    For the baffle you fabricate, could you give some detail? I have heard some folks use steel wool. I am interested in what you use, and how you attach it. The valve cover solution I referenced above is clean, but I like the look of yours without disturbing the valve covers.
     
  26. saltflats
    Joined: Aug 14, 2007
    Posts: 10,904

    saltflats
    Member
    from Missouri

    Read post #20 then you wont have to build a baffle.
     
  27. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,521

    gimpyshotrods
    ALLIANCE MEMBER

    My PCV valve is in the manifold, behind the carburetor, in a baffled grommet.
     
  28. Willy_P
    Joined: Mar 19, 2011
    Posts: 762

    Willy_P
    Member

    Thanks Saltflats, I missed that the first go around.
    Since I posted, I have been searching PCV posts and found a cool tech one from Tommy that describes the PCV operation quite well along with some parts photos.
    PCV valve for road draft tube block SBC
    http://www.jalopyjournal.com/forum/showthread.php?t=151629
    The fill tube on a 66 Corvette has a threaded bung on it for a pcv
    #
    GM put them into the fill tube on some sbc right from the factory. You can buy a chrome aftermarket one from Chevy2Only: http://www.parts123.com/parts123/yb....Z5Z5Z50000132A
    They also have them in black if you don't want bling.
    #
    Pcv Tech (by Tommy)
    http://www.jalopyjournal.com/forum/showthread.php?t=61376&highlight=tommy+pcv+system

    flamed abone wanted pix...posts 13, 19
    PCV time again!!
    http://www.jalopyjournal.com/forum/showthread.php?t=60593&page=1&pp=20
     
  29. saltflats
    Joined: Aug 14, 2007
    Posts: 10,904

    saltflats
    Member
    from Missouri

    You can make more H/P if you are not splashing hot oil on the bottom of the intake.
     
  30. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,521

    gimpyshotrods
    ALLIANCE MEMBER

    Lifter valley baffle:
    [​IMG]
     

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