Cats or no cats

Discussion in '96-04 - 2V Specific' started by Adam Vinnicombe, Sep 15, 2020.

  1. Werecow

    Werecow Well-Known Member

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    Care to elaborate?? It's been shown by Magnaflow and Flowmaster both that the performance drop from using their cats is negligible.. They were designed for lower emissions while not increasing backpressure. I plan on using a couple of 2 1/2 Flowmaster cats on mine when I'm able to go through the exaust on it so I can pass the visual part of the inspection here in Va..
     
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  2. Azhurel Mendes

    Azhurel Mendes New Member

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    I personally prefer dogs
     
  3. Fivestangs

    Fivestangs New Member

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    I went with a pair of Magnaflow cats on a BBK off-road H to cut down on the decibel level. It is still pretty loud with the 10 Series Flows the previous owner put on it! Plus no exhaust smell! I don't mind it on my older Mustangs but it just doesn't seem right on a "late model" like a '96 GT.

    I don't mind the exhaust smell from anything Foxbody back.
     
  4. Werecow

    Werecow Well-Known Member

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    I'm planning on either a set of 40's or 44's on mine, can't make up my mind on it which way to go tho... It's got a 351M right now, but I'm starting to lean towards a big block swap sometime in the future...
     
  5. DKblue98GT

    DKblue98GT Well-Known Member

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    I added Magnaflow 8" cats behind my longtubes this spring to pass emissions. Car is quieter and doesn't smell like gas and throws no codes.
     
  6. tvsn95

    tvsn95 New Member

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    about the only way you will ever see an increase in power /torque is if the back pressure counters some of the overlap of the cam. Back in the day carbs and some throttle body setups were so limited in the ability to adjust themselves that you could get an increase at high RPM due to the fueling going lean from the extra air passing through and not being metered.
    either way, its an old wives tale that has endured.
     
  7. ttocs

    ttocs Post Whore

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    I know I have talked to dyno people that have run cars with cut outs and said there was little to no difference with them open or closed. I could see it effecting how the car could run at idle or low rpm if its too short and the o2 sensor is close to the end.
     
  8. Werecow

    Werecow Well-Known Member

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    That's sorta like the common fallacy that every V-8 needs a dual 3in exaust to run well... In actuality unless you have over I think it was over 550 ci and run over like 7500 or 8500 you don't really need that much pipe.. 2 1/2 will do just fine, all you're doing is hauling around a lil bigger exaust.. it goes back to all I. C. Engines are nothing but an air pump and unless you are moving that much air you really don't need it..
     
  9. ttocs

    ttocs Post Whore

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    to big of exhaust can cause problems. I had a buddy back in the day that got a 95 gt that had 3.5 inch on it. It was loud, sounded like a really big tin can and ran like complete crap. Today I am sure the o2 sensor readings were off at low rpm from lack of back pressure and fresh air reaching them.
     
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  10. MustangChris

    MustangChris Post Whore Retired Staff SN95 Supporter

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    You'll see a lot of mish-mashed tech on this.

    Fact is:
    -OEM performance cars make 800+ horsepower with cats.
    -Kenne Bell did testing and saw no performance loss from cats. source

    Just put cats on the car.

    #1, you wont get nauseous sitting at a red light from the fumes of your own car.
    #2, you'll never have to worry about swapping it out for emissions testing.
    #3, it'll help make selling the car easier.
    #4, as someone who has to breathe the air your car is pumping full of exhaust, I'd appreciate it having cats.
    #5, aftermarket cats are literally, like, $50/ea.... What's the big deal?
     
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  11. Adam Vinnicombe

    Adam Vinnicombe Active Member

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    Ok I get your points :)
    I will be fitting cats but still trying to figure out what ones to fit, will £50 cats last ?
     
  12. MustangChris

    MustangChris Post Whore Retired Staff SN95 Supporter

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    Yes, they'll last. If you go through a reputable vendor and get a reputable brand and keep your paperwork, you'd probably be able to push them to give you a free replacement if they prematurely fail...

    https://www.summitracing.com/parts/flo-2230125
     
  13. Rocco_Roush

    Rocco_Roush New Member

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    i was just about to say a side exhaust gives extra flavor lololol

    but i got my car (2 months ago maybe) and as i was working out the kinks i got a deal on a upr x-pipe...catless...they don't make them anymore.

    anywho, i have a buddy with a lift and he had free time so we tossed it on. felt great.

    a few weeks later i did the plugs and coils (both motorcraft) because of a misfire. i believe i had 2 or maybe 3 misfiring because when i started her up w it with the new stuff she sounded totally different!!!

    anyway, the off-road x-pipe and the Roush side exhaust (magnaflow on mine) it does not sound obnoxious but sophisticated
     
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  14. evilcw311

    evilcw311 Most Evil Member! SN95 Supporter

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    Throw up a video of the exhaust.


    Sent from my iPhone using Tapatalk
     
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  15. Rocco_Roush

    Rocco_Roush New Member

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    I need to! Haven't had nice weather down here so I haven't had the chance to work on her or drive her around. But def on the list!