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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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    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

    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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    6 Questions / 9 Answers

    Ask a Question

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

    Hookshot

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

      AMMike

    Helpful (0)

    Is this the LM1's or LM2's?

    Trevor

    • These are the LM1's.

      JeffAM

    Helpful (0)

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

    SVTVERT

    • 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.

      AshleyK

    Helpful (0)

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

    BruceUBB

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

      Ricky36

    Helpful (0)

    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?

    JGSVTCobra

    • Trust me you'll want to install the resonators with the kit for the best sound and fitment.

      03cobraowner

    Show 1 more answer Helpful (0)

    Does this come with everything I need to install? Do I need any extra hangers or clamps or anything else with this system?

    styles

    • This SLP exhaust kit comes with everything you will need for the install!

      LisaS

    Show 2 more answers Helpful (0)

    People Who Bought This Item Also Bought

    Customer Reviews (41) Write a Review

    Overall Rating 4.8

    out of 5 stars

    Installation Time:Less than 1 Hour

    • Loudness / Volume 4.766667 4.8
    • Exhaust Note 4.9 4.9
    • Fit & Finish 4.7 4.7
    • Bang For Your Buck 4.666667 4.7



    • 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 (1)

    • 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 (2)

    • 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 (1)

    • 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 (1)

    • 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 (1)

    • 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 (1)

    • 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 (2)

    • 5/5

      Installation Time: Less than 1 Hour

      July 01, 2017

      Slp

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

      Jhonv

      Year: 2001 Submodel: Cobra

      Helpful (2)

    • 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 (1)

    • 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 (1)

    • 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 (1)

    • 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 (1)

    • 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 (1)

    • 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 (1)

    • 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 (2)

    • 5/5

      July 19, 2016

      loudmouth

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

      JuanN

      Year: 2004 Submodel: Cobra

      Helpful (3)

    • 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 (2)

    • 3/5

      Installation Time: Less than 1 Hour

      January 13, 2016

      Great cat-back but it is lacking in aesthetics

      The catback as far as fitment and ease of install is great. I love the sound. The major drawback that isn't very apparent from the picture is that the only parts of this catback that have any shine whatsoever are the resonators and the tips. One of the best parts about an IRS is having the pipes under the car really shined up as it looks amazing from behind. I don't know if SLP has changed anything, but the piping itself is extremely dull with lots of marks from the mandrel bending. It looks almost like mild steel piping. If it had a shine out of the box comparable to the Borla it would get 5 stars all day.

      MidnightMach

      Year: 2003 Submodel: Cobra Griffin, GA

      Helpful (5)

    • 5/5

      Installation Time: Less than 1 Hour

      October 29, 2015

      SLP Loudmouth LOUD!!!!

      OMG!!!!! All I can say is very loud sounding exhaust. If you like loud then get this exhaust. I freaking love this exhaust. No problems at all, fitment is good, awesome sounding exhaust.

      SVTCOBRA12

      Year: 2003 Submodel: Cobra Bryan, Texas

      Helpful (4)

    • 4/5

      Installation Time: Less than 1 Hour

      January 06, 2015

      tips and mufflers look great rest not quite as clean looking

      Loudmouth sounds great! Installation was easy. Mufflers and tips look great, the rest of the pipes look generic, not stainless steel. Thought it was all stainless steel like the MagnaFlow system. But sounds great and love the sound!

      svtoz

      Year: 2003 Submodel: Cobra Riverside, CA, USA

      Helpful (3)

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