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SLP Loudmouth Cat-Back Exhaust (99-04 Cobra)

Market Price $624.95 You Save 4% ($25.00)
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$599.95

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  • Item 23005
  • MPN# M31006

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Ship to: Ashburn - 20149
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    Features & Details

    • Rich, Throaty Exhaust Tone
    • Loudmouth "Shotgun" Race Resonators Included
    • Versatile Modular Design
    • 2.5" 409 Stainless Steel Tubing
    • 3.5" Polished 304 Stainless Steel Tips
    • Fits 1999 to 2004 SVT Cobra Mustangs
    More Power and Sound. This SLP system includes SLP's infamous Loudmouth "shotgun" race resonators that offer virtually no exhaust flow restrictions to free up more horsepower and to produce the most aggressive sound possible.

    Modular Design.   SLP's unique modular design allows you to quickly and easily switch out the mufflers or resonators to suit your driving needs. Along with the included resonators, the Loud Mouth system is compatible with all SLP mufflers and resonators including the bullet-type Loud Mouth II and the traditional-style PowerFlo Muffler.

    Superior SLP Construction. This SLP Cat-Back system is made from mandrel bent 2.5" 409 stainless steel tubing for its excellent non-restrictive flow characteristics and long life. The system ends with a brightly polished 304 stainless steel 3.5" tips, that are electro-marked with the distinctive SLP logo, giving a great finishing touch and a show quality look.

    Application. Designed to be a direct bolt on, this SLP Loudmouth catback will bolt straight up to the factory Mid-Pipe without any modifications required on the 1999 to 2004 IRS equipped SVT Cobra Mustangs to give it a rich, throaty sound.

    Fitment: 1999 2001 2003 2004 Details

    CA Residents: Warning: California's Proposition 65

    What's in the Box
    Hardware included:
    • (8) 2.5" exhaust clamps
    Installation Info
    Tech Specs
    Cat-Back Exhaust Specifications
    Piping Material: 409 Stainless Steel Tip Material : Polished 304 Stainless Steel
    Piping Size: 2.5" Tip Size: 3.5"
    Muffler Type: Straight-through Fitment: 1999-2004 Cobra Mustangs
    Will it fit my Mustang?

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    Questions & Answers (7)

    5 Top Rated Questions

    Hello do you know if I can put this on my 2004 mustang gt do you thing it will fit???

    • This exhaust is designed to fit a 99-04 Cobra only and will not work with a 2004 Mustang GT model. We do offer the SLP loudmouth and loudmouth II for the 04 Mustang GT which can be found here: https://www.americanmuscle.com/slpexhaust.htmland https://www.americanmuscle.com/slpmuloiica9.html. 

    Helpful (0)

    I have Kooks Headers and Kooks X Pipe will this bolt up together and not leak?

    • Hello, That is correct these are designed as a system.

    Helpful (0)

    Is this the LM1's or LM2's?

    • These are the LM1's.

    Helpful (0)

    SLP loudmouth or Borla ATAK?!?! and does this drone or sound bad w/o the resonators?

    • The SLP Loudmouth Cat-Back Exhaust feature a deep, throaty exhaust tone. The "shotgun" resonators that are included have virtually no restrictions which will offer more power and an aggressive sound. Without the resonators, you may receive a louder sound without some tone. The Borla ATAK Cat-Back Exhaust (99-04 Cobra), item # 29016, (http://www.americanmuscle.com/borla-atak-catback-9904-cobra.html) feature an extremely aggressive muscle car sound. These do not come with resonators like the SLP's do. Both of these Exhaust's should not feature drone.

    Helpful (0)

    Does the car need a re-tune with this catback? I have already have a CAI on the car.

    • The SLP Loudmouth Cat-Back Exhaust (99-04 Cobra) will not require a re-tune.

    Helpful (0)
    Post Your Question
    2 More Questions
    Do I have to install the resonators? Can I just leave out the resonators on this catback system so I can get more of a louder and throaty sound to this exhaust system? 2 answers
    Does this come with everything I need to install? Do I need any extra hangers or clamps or anything else with this system? 3 answers

    People Who Bought This Item Also Bought

    Customer Reviews (44) Write a Review

    Overall Rating 4.8

    out of 5 stars

    Installation Time:Less than 1 Hour

    • Loudness / Volume 4.787879 4.8
    • Exhaust Note 4.909091 4.9
    • Fit & Finish 4.727273 4.7
    • Bang For Your Buck 4.69697 4.7



    • 5/5

      Installation Time: Afternoon

      August 23, 2018

      the beast has awoke!

      I have this cat-back exhaust paired with an O/R Bassani X-pipe and holy smokes! installation was a breeze. bolts right up. Highly recommend this exhaust if you are looking for loud.

      KingCobra

      Year: 2001 Submodel: Cobra

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      July 12, 2018

      Recommended to everyone thinking about this.

      Easy to install and definitely gave my cobra a real cobra sound. Definitely happy with my purchase!

      JamesC

      Year: 2001 Submodel: Cobra

      Helpful (2)

    • 5/5

      June 10, 2018

      2004 cobra

      The slps are really what I was looking for a great deep sound for the price I like better than most expensive brands turn heads

      QuintariusG

      Year: 2004 Submodel: Cobra

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      April 05, 2018

      Slp lm1

      Ordered on Wednesday on my door step by Friday fast shipping with easy installation, if you want LOUD this is the exhaust for you!

      Franky

      Year: 2004 Submodel: Cobra

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      March 21, 2018

      Very good exhaust would definitely buy it again

      It bolted on good no problems definitely will recommend to other people.

      MichaelF

      Year: 2003 Submodel: Cobra

      Helpful (3)

    • 4/5

      Installation Time: Afternoon

      March 05, 2018

      Awesome sound!

      Easy to instal with a friend and some good Tools. Great sound!!

      BruceUBB

      Year: 2006 Submodel: Other

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      February 27, 2018

      SLP LM1 EXHAUST

      If you want a loud and rasp sound this is the exhaust for you I have o/r-bbk x pipe with this setup man it turns heads and people love the sound

      Richard

      Year: 2004 Submodel: Cobra

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      January 08, 2018

      Perfect

      Can’t go wrong with this cat-back. Easy instal and sounds amazing. Just the catback it self was aggressive. I combined the set up with a BBK off-road X-pipe and now is a beast. My 99 Cobra finally sounds the way it should.

      Figgs

      Year: 1999 Submodel: Cobra

      Helpful (2)

    • 4/5

      Installation Time: Afternoon

      December 01, 2017

      Exhaust

      Good product. love the sound. Wish it was all ready polished for the price.

      MatthewW

      Year: 1997 Submodel: Cobra

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      November 05, 2017

      Perfect sounds

      I just installed this exhaust last night with my brother, we both didn’t think it would sounds as loud as it is. It’s perfect not to loud and deep, or quiet just the best sounding system.

      RichieJ

      Year: 2001 Submodel: Cobra

      Helpful (4)

    • 5/5

      Installation Time: Less than 1 Hour

      July 01, 2017

      Slp

      Excellent products.. Americanmuscle is the best....................

      Jhonv

      Year: 2001 Submodel: Cobra

      Helpful (4)

    • 3/5

      Installation Time: Less than 1 Hour

      June 26, 2017

      Not bad

      When I bought my 04 cobra it had a flowmaster cat back on it I needed something louder so I went with the slp. Although the slp is an improvement I'm still not 100 happy I plan on replacing the stock H pipe with an offroad Mac prochamber hopefully this will get the job done.

      EverettC

      Year: 2004 Submodel: Cobra

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      May 31, 2017

      Best mod I have done!

      I installed this system on my 2004 Cobra and I could not be happier. This is what a mustang should sound like! I did the whole thing in my driveway with the rear on ramps. I recommend following the instructions from American muscle rather than slp.com. The hardest part of the install was getting the old system out of the rubber hangers. System is tame at cruising speeds but really wakes up when you get on it. I like that I can still hear my super charger over the exhaust. All in all a great setup for the price.

      PatrickS

      Year: 2004 Submodel: Cobra

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      May 30, 2017

      SLP LOUDMOUTH EXPERIENCE

      It sounds awesome really woke up my 03 cobra.Everything I was looking for in an exhaust .

      DanielG

      Year: 2003 Submodel: Cobra

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      May 20, 2017

      LOUD

      MINE SOUNDED GREAT, WOULD RECOMMEND TO EVERYONE, GREAT JOB

      LesJ

      Year: 2003 Submodel: Cobra

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      April 06, 2017

      Loudmouth!!!

      I ordered this exhaust and it came with in days of placing the order. Installation was quick and simple only thing is I had to log into the SLP website to get the info but besides that I love the exhaust. The tone and note sound great, not to loud at low idle but once I hit it she screams. Combined with my x pipe its a great deal the price was not to bad either. I'd buy again..

      KerryL

      Year: 2004 Submodel: Cobra

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      April 04, 2017

      Great exhaust

      This exhaust is super loud I have long tubes and off road h pipe,I am going to buy the loudmouth 2 mufflers to quiet it down a little,the quality of this cat back is great though and fits great!!

      JeremyD

      Year: 2003 Submodel: Cobra

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      December 15, 2016

      Mean

      Sounds beastly, I was scared it was going to be too loud but it sounds perfect. Good solid deep tone and a nice crackle in the higher rpms.

      Kobietk

      Year: 2001 Submodel: Cobra

      Helpful (3)

    • 5/5

      July 19, 2016

      loudmouth

      Easy to install, good price and awesome sound!! Thanks AM

      JuanN

      Year: 2004 Submodel: Cobra

      Helpful (7)

    • 5/5

      Installation Time: Afternoon

      March 07, 2016

      SLP makes a Great Product

      I have owned SLP exhaust before and never had a problem with it the fitment has always been great. I currently had Bassani exhaust on my car and it just fell apart. So I went with a exhaust that I have used before and was very pleased with

      03cobra

      Year: 2003 Submodel: Cobra

      Helpful (3)

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