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SLP Loudmouth Cat-Back Exhaust (1998 GT, Cobra)

Item 23006
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$574.95

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    Features, Video & 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 1998 GT and Cobra Mustangs

    Review & Installation Video

    Review & Install Video

    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 1998 GT or SVT Cobra Mustangs to give it a rich, throaty sound.

    Fitment: 1998 Details

    MPN# M31011

    CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

    What's in the Box
    Hardware included:
    • (4) stainless steel band 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: 1998 GT and Cobra Mustangs
    Will it fit my Mustang?

      Customer Photos (14) Submit Your Photo

      View All 14 Photos

        Questions & Answers (10)

        5 Top Rated Questions

        How much HP will it add?

        Do I have to buy something else to install in my car? My car is stock

        • 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 1998 GT or SVT Cobra Mustangs to give it a rich, throaty sound.

        Helpful (0)

        I have this system, I’m looking into a maximum motorsports Panhard Bar. Will it clear?

        • We have not yet test fit this combination and are unable to confirm co fitment.

        Helpful (0)

        Will this exhaust fit a 97 Cobra swapped new edge (99 GT) with a BBK O/R X pipe ?

        • This part has not been tested on this kind of swap for confirmation on fitment.

        Helpful (0)

        Will this fit a 1995 gt

        • Unfortunately this exhaust will not fit a 1995 Mustang GT. It will only fit the 1998 Mustang GT and Cobra models. However, we do offer a SLP loudmouth exhaust for the 94-97 Mustang GT models which can be found here: https://www.americanmuscle.com/slp-loudmouth2-catback-94-97.html.

        Helpful (0)
        Post Your Question
        5 More Questions
        Will this fit with an bbk o/r h pipe? 1 answer
        Can you fit flowmaster mufflers on this catback system later on after you purchase it and put it on the car? 1 answer
        Will this fit a 98 mustang with a 5.0 swap? 1 answer
        will this cat back exhaust turn on my check engine light? im keeping my factory mid-pipe. 1 answer
        Will these fit with long tube headers and a shorty x pipe or will I have to get a mid x pipe? 1 answer

          Customer Reviews (27) Write a Review

          Overall Rating 5

          out of 5 stars

          Installation Time:Afternoon

          Installation Cost:$100-$250

          • Loudness / Volume 4.923077 4.9
          • Exhaust Note 4.846154 4.8
          • Fit & Finish 4.923077 4.9
          • Bang For Your Buck 4.615385 4.6



          • 5/5

            Installation Time: Less than 1 Hour

            December 25, 2018

            SLP Catback

            I recently installed the SLP Catback system on my 98 Cobra. The fit was perfect! I can't comment on the sound of it yet because I won't be firing up the Cobra until spring. However, I'm sure its going to be very loud considering I have it paired with an UPR x-pipe! It does look very aggressive under the car. A lot meaner looking then the wimpy factory tail pipes. I would recommend this system just because of the looks it provides alone!!

            Bombard32

            Year: 1998 Submodel: Cobra

            Helpful (3)

          • 5/5

            Installation Time: Afternoon

            June 20, 2018

            Very loud!!

            Great fit.easy to install,looks geat,sounds great!

            Matt

            Year: 1998 Submodel: GT

            Helpful (5)

          • 5/5

            Installation Time: Afternoon

            June 06, 2018

            SLP LM1

            Has an awesome tone, install only took about 2 hours with no issues or confusion, and is a great start to putting a whole new exhaust system in!

            GarrettM

            Year: 1998 Submodel: GT

            Helpful (6)

          • 5/5

            March 08, 2018

            Awesome

            They were easy to install and they sound amazing and over all they look really good on the car

            TravisS

            Year: 1998 Submodel: GT

            Helpful (5)

          • 5/5

            December 18, 2017

            SLP Loudmouth

            Pack very well!! Looks awesome can't wait to install!

            BrettR

            Year: 1998 Submodel: GT

            Helpful (8)

          • 5/5

            Installation Time: Afternoon

            December 07, 2017

            Love it

            Looks good and sounds amazing. Easy install tips look great. All together took about 1hr 30 mins

            DennisS

            Year: 1998 Submodel: GT

            Helpful (5)

          • 5/5

            Installation Time: Shop Install

            Installation Cost: $100-$250

            October 22, 2017

            Slp loudmouth exhaust

            I love it and it has a deep sound ,when u gas on it it gets louder or u can crip around and hardly hear it I love the way it sounds.

            TylerH

            Year: 1998 Submodel: GT

            Helpful (8)

          • 5/5

            Installation Time: Afternoon

            October 01, 2017

            Amazing

            Doesn't come with new flange bolts (3/8) but it's a amazing cat back system. Would recommend to a friend.

            Phillip

            Year: 1998 Submodel: GT

            Helpful (6)

          • 5/5

            Installation Time: Less than 1 Hour

            April 26, 2017

            Great Choice!!!

            SLP Loudmouth was a great choice! It's pretty loud and will draw attention. I debated on getting it for a few months because of its loudness, but decided to dive right into it. I am even more excited to drive my 98 Cobra now because it's extremely loud sound. It's worth every cent and the quality is great!!!

            QuintonT

            Year: 1998 Submodel: Cobra

            Helpful (6)

          • 5/5

            Installation Time: Afternoon

            March 20, 2017

            98 mustang GT SLP

            Sounds perfect had to line up some of the pipes but got it right where I wanted it

            TaurusY

            Year: 1998 Submodel: GT

            Helpful (8)

          • 5/5

            Installation Time: Less than 1 Hour

            May 16, 2016

            Great Exhaust

            Took 1 Hour to install with Jack stand in the rear. Simple hand tools. Sounds outstanding with my Catted Bassani X. Tips are awesome, everything slides right together. Great Job SLP and American Muscle for get shipped fast.

            Drew

            Year: 1998 Submodel: Cobra

            Helpful (7)

          • 5/5

            Installation Time: Afternoon

            May 14, 2015

            Great Exhaust.

            Fit perfect. Quality is top notch. Love the look. If you want loud then ive never had a louder exhaust.

            vnmsgt

            Year: 1998 Submodel: Cobra Orlando

            Helpful (8)

          • 5/5

            Installation Time: Less than 1 Hour

            February 12, 2012

            SLP Loudmouth

            Exhaust sounds great and has an awesome tone. Really aggressive. Sounds amazing with my upr catted x pipe. Install was pretty easy just had to bend the pipes a little for a perfect fit. Thanks American Muscle

            Gary27

            Year: 1998 Submodel: GT

            Helpful (8)

          • 5/5

            May 15, 2011

            Very loud with great tone

            If your thinking about it just buy it. Though it is very loud when you step on the gas, if you keep your foot out if it, this kit will give you a very deep hollow and throaty rumble, but stuff it and it starts screaming. All in all a great set of pipes, though if your not into making the most noise possible, you could go with the LM 2 system, its a little more toned down and reasonable. A friend of mine heard me revving at a car show, he said "it just gave me a headache, that think is stupid loud!"

            Chase

            Year: 1998 Submodel: GT

            Helpful (7)

          • 5/5

            October 09, 2010

            SLP rocks

            Well all i can say is that SLP headers, x-pipe, and catback are very amazing in all areas. My mustang still has that rich deep sound of a mustang which i was very concern about, but not with SLP. My buddy has a 98 camero with another system on and had to put cut out on to be louder. So yes SLP Loudmouth are very loud. otherwise very easy to install and it was worth very penny.

            Ryan Cawley

            Year: 1998

            Helpful (8)

          • 5/5

            July 17, 2010

            wow...

            Well, bought this with a catless x pipe. pretty sure open headers would be quiter... lol. but i get complements from everyone, just sounds so mean. give in to temptation and get it. so worth it.

            Chad

            Helpful (9)

          • 5/5

            May 07, 2010

            Blastin. your ears off.

            The most important word is LOUD. just how i like it. bolted up real nice. to x-pipe. good clearance from the ground. everything fit good and tight. nice idle. nice cruz sound. then step on it and your breaking windows. setting off cars and maybe house alarms' lol cuz its 'LOUD' first day i took it for a test run got pulled over. in friends driveway. you mite see me on youtube lol. that was a warning. second day got pulled over got a warning ticket. lets see how many tickets i get this yr. lol

            John s.

            Helpful (9)

          • 5/5

            May 07, 2010

            Blastin your ears off.

            very good catback sys can really feell the power kick in at 5000 and above. fit and finish very good. it screams get out my way when you step on it. just how i like it. Nice.

            John s.

            Helpful (9)

          • 5/5

            April 15, 2010

            slp loudmouth catback

            Great product. It really roars when you open it up.

            Dan Pompe

            Helpful (7)

          • 5/5

            February 11, 2010

            YOU WANT LOUD!

            THIS IS THE FIRST AND ONLY EXAUST YOU WILL EVER NEED FOR YOUR MUSTANG..2 THUMBS UP!

            JEREMY

            Helpful (7)

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