Off road Down pipes? Experiences please.

Discussion in 'Generation 4 - Performance Upgrades' started by kcobra, Jan 21, 2021.

  1. kcobra

    kcobra SHO Member

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    I currently have a set of high flow catted down pipes and thinking of going off-road down pipes. How bad is the smell and should I just keep my current ones?
     
  2. yaycandy

    yaycandy The Slack Jawed Yokel

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    Oh it will smell like gas. Tell ya that as im straight pipes and full catless. Wont smell it in car. Just in the back mostly when cold.
    Sure beats cadillac derverter smell
     
  3. Ta2dResqr

    Ta2dResqr SHO Member

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    How bad do classic cars smell? Cars went for 75 years without them and smelled fine. Often without a exhaust sniffer or looking under the car, you cannot tell if a convertor is missing. Motorcycles just started putting them on in the last decade or so.
     
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  4. FiveLeeter918

    FiveLeeter918 Ortiz Performance Sales Sponsoring Vendor

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    with proper tuning you can almost eliminate the smell. Like yaycandy said, you can smell it on start up if behind the car but after that I don't notice it.
     
  5. FiveLeeter918

    FiveLeeter918 Ortiz Performance Sales Sponsoring Vendor

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    A lot of tuners leave cat protection on even when the cats are removed and it causes the car to run rich, giving a raw fuel smell. I've ridden in some cars that make your eyes water. Pretty sure we were getting some carbon monoxide poisoning too haha.
     
  6. yaycandy

    yaycandy The Slack Jawed Yokel

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    Ppe catless dont throw cel for o2s. American racing (livernois) catless pipes do, but a tune can tune it out. I had both, american racing ones first, ppe is larger diameter but bigger isnt always better. I ran my car on a dyno with my tuner since he is local to me and the car actually made more power on the smaller diameter american racing ones. With stock turbos. Probably why they cost more.
     
  7. Chuck Johnson

    Chuck Johnson Member

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    Go ahead with the Catless so you can sell me the Catted ones...lol
     
  8. FiveLeeter918

    FiveLeeter918 Ortiz Performance Sales Sponsoring Vendor

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    you mean PP catted don't throw a CEL? It'd be impossible for a catless pipe to not throw a CEL unless the CEL was turned off in the tune.
     
  9. yaycandy

    yaycandy The Slack Jawed Yokel

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    The ppe catless never threw a cel for me. Maybe my car is weird, but some other people it never threw a cel for either. Didnt really matter, easy fix if it would have. Just like my stock bov wiring, they can be switched off by Brad for my HKS bov
     
  10. FiveLeeter918

    FiveLeeter918 Ortiz Performance Sales Sponsoring Vendor

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    man that BOV switch is becoming a PITA. Finding more and more strategies that don't have that switch activated. We're working with Mike in the other thread on a tune as well and his strategy is unresponsive to the switch. Very annoying and SCT has no desire to fix it since it's not a GT500.
     
  11. yaycandy

    yaycandy The Slack Jawed Yokel

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    Just zip tie the rear bov to the bar above it like i did for months. Lol. But it worked
     
  12. FiveLeeter918

    FiveLeeter918 Ortiz Performance Sales Sponsoring Vendor

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    yep, that was our final recommendation.
     
  13. skyshadow07

    skyshadow07 On a mission to get below 4000lbs

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    The reason I changed to catted from non was not the smell, the smell was hardly noticeable. It was the sound. The cats cut a ton of exhaust sound. Without them, I was unable to get my car to not be insanely loud at rpms above 25oo.
     
  14. DGrot777

    DGrot777 Member

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    What was the exhaust looking like behind the cats? I know you have a side dump lol. Catless sounds pretty quiet when everything else is still on the car.
     
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  15. skyshadow07

    skyshadow07 On a mission to get below 4000lbs

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    I have a side dump, 2-1 with two resonator style mufflers before the convergence. But before I was running the stock piping, minus the first muffler after the 3rd cat and it was very loud.
     
  16. DGrot777

    DGrot777 Member

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    That 3rd cat and muffler keep a lot of the rasp away. I know you can gain some hp deleting them, but for sound purpose those will probably permanently stay on my car.
     
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  17. skyshadow07

    skyshadow07 On a mission to get below 4000lbs

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    I have pretty great sound now with 400 cel cats on custom downpipes going 2-1 after two resonator mufflers then running through oval pipe to dump in front of the passenger rear wheel. The cats helped a ton!
     
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  18. kcobra

    kcobra SHO Member

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    Installed off road downs. Literally no sound difference from my high flow catted ones. Very happy. I do hear spooling more. My catted Thunderstorms are now for sale.
     
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  19. CCXVI

    CCXVI SHO Member

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    Man I thought I was the only one with a side exit! Mine was right behind the front wheel though
     
  20. skyshadow07

    skyshadow07 On a mission to get below 4000lbs

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    You have a side dump? pics
     

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