Oem Catalytic Converter vs. High Flow Cat..

Discussion in 'Off Topic' started by AE86Lover, Apr 17, 2006.

  1. AE86Lover

    AE86Lover Member

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    I need a catalytic converter for my car and i was wondering, what the main differences are in a high flow catalytic converter..

    PDM is pleased to announce a brand new product. Teamed with Magnaflow, PDM is able to offer a bolt-in replacement high flow 2.25" Catalytic Converter for the Toyota Corolla.
    Toyota Corolla High Flow Cat

    Over time, your stock catalytic converter will begin to plug up from residual oil, and from cleaning up the carbon monoxide from your hard working engine?s exhaust. Renew your car?s performance with true high flow catalytic converter that keeps the environment clean, and adds performance back to your Corolla.


    Mirror finish stainless steel, high-flow catalytic converter with proper Toyota Corolla flanges welded in place. These are not universal fit type catalytic converters which rotate and slide around, but specific high-flow cats that PDM cuts to length, and welds 3/8? thick, 2.25? i.d. beefy steel flanges.

    http://www.pdm-racing.com/products/imag/highflowcat_web.jpg

    Features of this high quality Cat include:


    - Recessed Cushioning Mat to help hold the catalyst firmly in place and protect it from direct exhaust flow.
    - Special ½? lap joint to help create a smooth transition in and out of the converter
    - 409 16 gauge stainless steel neck and body to resist corrosion and high operating temperatures.
    - Mirror finish stainless steel heat shield.
    - Quad ribbed body for strength from heat
    - Seam welded interior on top and bottom to help minimize distortion
    - High flow honeycomb catalyst for optimum flow.

    Comes complete with 2 exhaust gaskets, and hardware to bolt in as a direct replacement for your OEM Toyota Catalytic converter.


    http://www.pdm-racing.com/products/toyota_corner.html
     
  2. NutBucket

    NutBucket Lifer

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    If it isn't metallic substrate its not really a high-flow cat. That said, unless your stock cat is old and clogged then any cat will be better. Honestly, this cat vs. a "normal" cat is not going to make a noticeable difference on performance.
     
  3. Heisenberg

    Heisenberg Lifer

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    Yeah, you're not going to see any noticeable gain just by swapping in a "high flow" cat. If you had significant engine mods and a bigger exhaust , then a high-flow cat would be justified.
     
  4. AE86Lover

    AE86Lover Member

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    what about in terms of how much CO it absorbs? Would the HIGH FLOW absorb the same amount as a regular CAT?
     
  5. Heisenberg

    Heisenberg Lifer

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    Well, first of all a cat doesn't absorb CO. It converts CO to CO2, and converts other exhaust gases as well. Ideally, you would see the same conversion efficiency out of a high-flow cat that you would of an OEM. In reality, most high-flow converters probably sacrifice some efficiency for performance.
     
  6. AE86Lover

    AE86Lover Member

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    thanks for input.
     
  7. blahblah99

    blahblah99 Platinum Member

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    It's not going to make a different on a car that's pushing 100rwhp. If you turbo it up, however, it will be a different story.
     
  8. fbrdphreak

    fbrdphreak Lifer

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    Don't waste your money.

    In terms of efficiency converting CO to CO2, I think its a matter of surface area. TMK, a cat converts CO to CO2 via the hot metal inside the cat. When the gas reacts to the super hot metal, the reaction produces CO2 (trying to remember high school chemistry...). Accordingly, it seems to me like the surface area of the metal (thus the amount of metal contacting the CO to convert it to CO2) would be the appropriate measure of its efficiency. If I had to guess, a high-flow cat probably produces higher emissions than a standard cat.
     
  9. NutBucket

    NutBucket Lifer

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    Besides, as far as legality goes you might as well run catless vs. most high flows. Not that they don't work...just not "approved".

    Welcome to Cali.......
     
  10. Insane3D

    Insane3D Elite Member

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    My Mustang ran cleaner on the emissions test (when we had that here) without the four stock cats than it did with them. That being said, those magnaflow cats are top notch. If you are going to get one, I know a site that sells Magnaflow stuff cheap and free shipping...
     
  11. tontod

    tontod Diamond Member

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    I have an Audi A4 1.8T turbo, and it made a small difference in performance. I also have an aftermarket turbo back exhaust, helps the turbo spool up a bit faster. But for N/A engines, not sure how much difference just a high flow cat will make.
     
  12. NutBucket

    NutBucket Lifer

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    The turbo back makes more of a difference than the cats. Get the tune to match;)
     
  13. tontod

    tontod Diamond Member

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    You are right, the gains with the high flow cat are small compared to the exhaust, but a gain nonetheless :D

    Here are a couple of clips:

    Standstill revs

    Driving away
     
  14. tontod

    tontod Diamond Member

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    Its all about lowering restriction in the exhaust, higher airflow is good ;)

     
  15. Viperoni

    Viperoni Lifer

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    QFT!

    I had a magnaflow highflow cat on my 92 Topaz V6 5speed, original o2 sensors, and it passed etest with flying colours. Picked up performance too, I highly recommend them!
     
  16. codeyf

    codeyf Lifer

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    Yeah, I wouldn't do it unless you needed to.

    Case in point, the exhaust on the '95 Accord I had rusted out. The cat was rusted to the exhaust as well. So I replaced them with a Magnaflow Cat and RS*R exhaust. Cost half of what all new stock parts would've cost :)