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Is a cat necissary?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by johnnieg, Apr 10, 2003.

  1. johnnieg

    johnnieg 1/2 ton status

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    How much does a catalytic converter drop emissions? I did my emissions about a month ago and the readings are way below the limits.
    HC ppm limit=400 idle=135 2500rpm=41
    CO% limit=1.50 idle=.69 2500rpm=.38
    Can I gut it and still pass? /forums/images/graemlins/k5.gif
     
  2. 90K5

    90K5 1/2 ton status

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    cat does a lot...without it those numbers will be really high...like HC's in the 2000's and CO% in the 10-20...thats what mine was putting out whit a bad cat.
     
  3. Bubba Ray Boudreaux

    Bubba Ray Boudreaux 1 ton status

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    No, a cat is not necessary, my dawgs hate them. /forums/images/graemlins/grin.gif
     
  4. 84_Chevy_K10

    84_Chevy_K10 Banned

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    Don't gut it. You can put a pipe through it, but don't gut it.

    You'll most likely still pass without it. The cat does drop emissions dramatically, but I bet you can still pass without it if your engine runs the way it should.

    A bad cat is worse than no cat cause it'll make your engine run like $hit. A properly running engine that's 15+ years old should pass all but California's standards without a cat IMO.

    Do this at your own risk. It may not pass.
     
  5. bryguy00b

    bryguy00b 3/4 ton status

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    we dont gatta worry bout that stuff here..my dad puts the inspection stickers on our vehicles! /forums/images/graemlins/thumb.gif me and my dad have duals with out any cats..just mufflers and thats it.. i got headers,duals with dynomax's..and thats it no tailpipes ur nothin... sounds awesome too!
     
  6. dyeager535

    dyeager535 1 ton status Premium Member

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    If the things working correctly, and not too old, don't waste your time.

    Newer cat converters cause very little, if any restriction, and since you have to pass emissions, why make it hard on yourself?

    Again, thats if the cat is good.
     

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