GT40p Heads and Cats

Discussion in '94-95 5.0 - Specific' started by Vettn71, Dec 15, 2014.

  1. Vettn71

    Vettn71 Member

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    1995 GT with GT40p heads. I know on the stock heads there is a tube that runs between the heads as part of the Thermactor system. I need to retain the cats for emissions. Since this tube supplies air to the heads during warm up, is it needed after that? Will the car set codes if it is not hooked up? Will it make a difference in emissions?

    TIA

    Jim
     
  2. CC'S95GT

    CC'S95GT Legend

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    I know it won't throw a code. My smog pump is bypassed currently.
    I don't think it will make a difference with the sniffer at all. I am planning on confirming this in Feb when my emission test is due.
    Depending on how hard they look, you might fail because it's not connected. Maybe keep the smog pump and just the tube going to the cats if you have to.
     
  3. Vettn71

    Vettn71 Member

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    I've heard you can just set it back there for emissions. They'd have yo look really hard to see it. My concern is with emissions. The system is directing air at the cats when it warms up, but not certain what pumping air into the heads does when the car is cold

    jim
     
  4. CC'S95GT

    CC'S95GT Legend

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    IDK specifically what it does for the heads either. I've been running with the smog pump bypassed for a couple months now and have noticed any differance in performance or exhaust smell.
    If mine passes with the pump bypassed then the pump and all the hoses will be coming out.
     
  5. Vettn71

    Vettn71 Member

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    Please let me know how that works out. I just had mine smog tested and it came in real low, sothatmight help

    jim
     
  6. Vettn71

    Vettn71 Member

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    Since my heads are at the machine shop I just am having them punch the holes for the crossover pipe. Problem solved!

    jim
     
  7. ttocs

    ttocs Legend

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    I thought it would throw a code if the tune wasn't set up for it to go with out it and any CEL will fail you from inspections quick.
     
  8. CC'S95GT

    CC'S95GT Legend

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    There's no sensor on the smog pump. It's only real purpose is to warm the cats up faster at cold start..
    EGR vlv will throw a code