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WANTING TO STRIP OFF PCV SYSTEM

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by JAKDUPBLUK5, Jun 9, 2003.

  1. JAKDUPBLUK5

    JAKDUPBLUK5 Registered Member

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    I'm thinking of stripping the PCV system off of my '87 5.7 TBI K5. JUst becuase it's smog crap, and I have a feeling its not helping my oiling system with extra venitaltion being forced into the crankcas; especially with a recently installed hihg volume oil pump.
    What would the good and bad things be as a result of taking it all off? /forums/images/graemlins/k5.gif
     
  2. JAKDUPBLUK5

    JAKDUPBLUK5 Registered Member

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    Come on, anyone?
    /forums/images/graemlins/k5.gif
     
  3. Shaggy

    Shaggy 3/4 ton status

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    <font color="green"> There is absolutely no reason to pull the PCV off. It will not increase the performance of your engine at all. I don't understand why people have this aversion to smog control devices of any sort. If the stuff works right then it doesn't hurt anything. What harm is tehre in keeping it there, except for the fact that it's one of those evil smog devices? /forums/images/graemlins/rolleyes.gif </font>
     
  4. JAKDUPBLUK5

    JAKDUPBLUK5 Registered Member

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    maybe i wasnt specific enough
    i was wondering if removing it would change the pressure in the crankcase and affect the oil pressure or pickup or oil recovery into the pan at all. I know it would do anything rel performance wise. Also, would it screw up the evil computer controlling my truck? /forums/images/graemlins/k5.gif
     
  5. Shaggy

    Shaggy 3/4 ton status

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    <font color="green"> PCV valves have been around for quite a while, I think that if they caused oiling problems they would have fixed that by now. I've never personally heard of them causing any problems with anything on an engine. That doesn't mean that they haven't caused problems, I'm just saying that I doubt it. Not sure if it would mess with the evil computer, but I wouldn't be surprised. /forums/images/graemlins/tongue.gif </font>
     
  6. monte0172

    monte0172 1/2 ton status

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    P.C.V. Positive Crankcase Ventilation. The PCV valve sucks air out of your crankcase creating a vacuum inside your motor. What that does is keep your engine sealed and not spewing out oil everywhere. Now when your rings are shot and you have so much blow by that the pcv cant keep up this is why you get major oil leaks. Just some good to know info from and engine builder!!!
     
  7. Goober

    Goober 1/2 ton status

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    Taking off your PCV system will probably not provide you with any performance benefits but it could be the cause of some really nasty problems.

    Positive Crankcase Ventalation (PCV) is not necessarily a "smog" item. It's necessary for an engine for a few different reasons.

    First, all internal combustion engines have blowby past the piston rings especially when cold. That blowby contains fuel vapors that will mix with your oil. Gasoline is a excellent solvent and will thin your oil out and break it down over time. Thin, broken down oil will not lubricate your engine ..... that's bad.

    Second, the blowby will create a high pressure area inside your crank case that will try to push oil out every gasket and seal. Having a functioning PCV system allows all the fuel vapors and blowby gasses to get removed from your crank case and re-introduced into your combustion chambers to get one more chance to burn. It also creates a low pressure area inside your crank case which will tend to suck oil back into the engine rather than force it out.


    PCV systems are used on everything from regular cars / trucks to Winston Cup cars and Top Fuel Dragsters. They have an important job to do so make sure your PCV system is working properly rather than removing it.


    [​IMG]
     
  8. JAKDUPBLUK5

    JAKDUPBLUK5 Registered Member

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    THANKS. Now thats the kind orf answr i was lookin for
    /forums/images/graemlins/k5.gif
     
  9. Goober

    Goober 1/2 ton status

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    [ QUOTE ]
    THANKS. Now thats the kind orf answr i was lookin for
    /forums/images/graemlins/k5.gif

    [/ QUOTE ]


    Glad to help.


    Where are you in Washington?
     
  10. wrathORC

    wrathORC 1/2 ton status

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    The PCV system doesn't rob any horsepower. It just creates a moderate amount of vacuum lines running all over.

    First, you should have a system to remove vapor from the gas tank. It's always a good idea to do that. The charcoal canister is a good thing as long as it works properly. The bottom covered with mud is not the way to get it to work properly.

    Second, it produces a vacuum in the crankcase. This removes gas vapor from the crank case and keeps your oil from absorbing it. It will make your oil last longer. This is only true if you have a good system of filtering the air entering your crankcase. Those breather elements in your air cleaner aren't my idea of good.

    That vacuum in the crankcase also does some other neat things. It keeps the oil in the engine. There would be oil leaking out if the crankcase wasn't equalized or had a vacuum on it. One of the favorite places to have a leak is on the harmonic balancer end of the crank. It makes the rings seal better by lessening the pressure observed by them from the crankcase. Next, the more vacuum you have in a crankcase the less air there is to have windage losses.



    Now, my question is, what do supercharged or turbocharged motors do for vacuum? Do they run a vacuum pump like what you'd find on some Cadillacs? Can't exactly get vacuum for powerboost brakes or your heater controls if you don't have a vacuum source.
     
  11. JAKDUPBLUK5

    JAKDUPBLUK5 Registered Member

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    Goober, i Live in ellensburg for school but I'm from renton right near ya. /forums/images/graemlins/k5.gif
     
  12. gravdigr

    gravdigr 1/2 ton status

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    [ QUOTE ]
    First, you should have a system to remove vapor from the gas tank. It's always a good idea to do that.

    [/ QUOTE ]

    Sorry for the hijack but it seemed the original post was answered and one of the answers brought up a question of my own. I am building a 79 blazer and most everything under the hood was gone including the charcoal canister. Are there any options for gas tank venting other than a charcoal canister? Is there a such thing as a vented gas cap?
     
  13. JAKDUPBLUK5

    JAKDUPBLUK5 Registered Member

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    yeah theres vented gas caps. they been aropund for decades. just ask somone at your local auto parts store. (preferebaly not the retards who work at schucks) and as for the pvc you can just put a breather cap on the valve cover.
     
  14. dyeager535

    dyeager535 1 ton status Premium Member

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    [ QUOTE ]
    The PCV system doesn't rob any horsepower. It just creates a moderate amount of vacuum lines running all over.

    [/ QUOTE ]

    All the GM vehicles I deal with run one hose from the PCV to the carb base. /forums/images/graemlins/confused.gif Everything else is AIR, advance, EGR, etc.
     
  15. JAKDUPBLUK5

    JAKDUPBLUK5 Registered Member

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    welll i have A.I.R. on miy truck and i took it off. ANythign bad there except for the power and gas mileage i gained which was good?
    /forums/images/graemlins/k5.gif
     
  16. wrathORC

    wrathORC 1/2 ton status

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    Depending on vehicle it might have three ports on that PCV valve (mine has three). The vapor system works off vacuum so it has at least two lines running to the canister...
     
  17. dyeager535

    dyeager535 1 ton status Premium Member

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    [ QUOTE ]
    welll i have A.I.R. on miy truck and i took it off. ANythign bad there except for the power and gas mileage i gained which was good?

    [/ QUOTE ]

    Unless you put your truck on a dyno, or took it to the track, there is no way a properly operating AIR system increased ANYTHING that you could see or feel. Period.

    You should probably get some good information before making decisions like that. You might actually find out how much power this stuff really "robs".
     
  18. wrathORC

    wrathORC 1/2 ton status

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    I can't tell whether you're confused or not. He stated that by removing the AIR system he gained mileage and horsepower. Common sense says if it ain't a supercharger then anything hooked to the crank robs horsepower.
     
  19. JAKDUPBLUK5

    JAKDUPBLUK5 Registered Member

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    yeah dyagear you need to rethnk what you said. not only was the air pump hooked up to the crank robbing power there, the air injsection system that it runs injects air directly into the exhaust , thus restricing the flow of exhaust out of the engine as itd be fighitnt he rest of the exhaust for space in the tubing etc. Any idiot knows that to increase power and gas mileage you increase and ease flow of air into and out of the engine. I'm sure you just misread it or suddenyl stopped thjinkin like a real k5 guy. i do crap like that sometimes too. /forums/images/graemlins/k5.gif /forums/images/graemlins/k5.gif /forums/images/graemlins/k5.gif
     
  20. JAKDUPBLUK5

    JAKDUPBLUK5 Registered Member

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    hey dont gimme guff. I been building and racing cars, trucks and engines, since i was barely outta elementary school. I know power and what im tlakin about. And i was raised by straight speakin gruff talkin americans so ill say whatever the heck i want. (clean enough for your G rated tastes sir?) /forums/images/graemlins/k5.gif
     

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