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

Market Price $598.95 You Save 4% ($24.00)
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  • Item 23025

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    Features & Details

    • Rich, Throaty Exhaust Tone
    • Loudmouth II "Bullet-Type" Race Mufflers Included
    • Versatile Modular Design
    • 2.5" 409 Stainless Steel Tubing
    • 3.5" Polished 304 Stainless Steel Tips
    • Fits 1998 GT and SVT Cobra Mustangs
    More Power and Sound. This SLP system includes SLP's famous Loudmouth II "Bullet Style" race mufflers for minimal restriction, increased horsepower and an aggressive tone, that are only second to the Loudmouth "shotgun" race resonators for sound.

    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 bullet mufflers, the Loud Mouth II system is compatible with all SLP mufflers and resonators including the shotgun style Loud Mouth Resonators 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 II catback will bolt straight up to the factory Mid-Pipe without any extra modifications required on the 1998 GT and SVT Cobra Mustangs to give it a rich, throaty sound.

    Fitment: 1998 Details

    MPN# M31011A

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    • (2) Bullet Style Muffler
    • (2) Exhaust Tip
    • (2) Flow Tube
    • (2) Over Axle Pipe
    • (2) Axle-Back Pipe
    • (2) Hanger
    • (2) Hanger Spacer
    • (8) Clamp
    • (2) Flange Connection
    • (4) Bolt
    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?

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    Customer Reviews (11) Write a Review

    Overall Rating 4.9

    out of 5 stars

    Installation Time:Afternoon

    • Loudness / Volume 4.125 4.1
    • Exhaust Note 5 5
    • Fit & Finish 5 5
    • Bang For Your Buck 4.625 4.6

    • 5/5

      April 19, 2019

      Perfect sound

      Perfect Rowdy sound , paired with a off road h pipe .


      Year: 1998 Submodel: GT

      Helpful (0)

    • 5/5

      Installation Time: Weekend

      March 24, 2019

      SLP Loud Mouth II

      I'm very satisfied with the level of sound. I still have stock cats, but nevertheless the deep sound is amazing. Installation was easy. the main challenge was to remove old rusted bolts.


      Year: 1998 Submodel: GT

      Helpful (0)

    • 5/5

      Installation Time: Afternoon

      May 03, 2018

      98 Cobra

      Sounds great install was not to bad the hardest part is getting the old exhaust off


      Year: 1998 Submodel: Cobra

      Helpful (5)

    • 5/5

      Installation Time: Afternoon

      January 12, 2018

      Sounds beautiful

      Its so loud i love it. I paired it with the bbk offroad h pipe and my car has never sounded healthier.


      Year: 1998 Submodel: GT

      Helpful (5)

    • 5/5

      Installation Time: Less than 1 Hour

      July 04, 2017

      Great sound

      Perfect fit, great deep sound, could be louder... the kit is made exceptionally well. Proper fit just takes a lot of time to get everything to line up. Having an OCD friend helps.


      Year: 1998 Submodel: GT

      Helpful (5)

    • 5/5

      Installation Time: Afternoon

      March 14, 2017

      Great fit and awesome sound

      This is a super easy to install kit, and the tips look great. This doesn't come with any instructions, but it's pretty easy to figure out. The fit and finish is exactly what I was looking for.


      Year: 1998 Submodel: GT

      Helpful (4)

    • 5/5

      Installation Time: Afternoon

      November 21, 2014

      Perfect note SLP 2

      Paired this with off-road bbk x pipe and it's the perfect tone, not too loud but let's people know you mean business!


      Year: 1998 Submodel: GT Dinwiddie, VA

      Helpful (7)

    • 5/5

      Installation Time: Afternoon

      February 25, 2012

      Great Product!

      I installed by myself in 4 hours from start up to clean up with the car on jack stands. This exhaust has a mellow tone under normal driving and is somewhat loud under hard acceleration. I have a catted SLP x-pipe & this exhaust is quieter than the rusted out Flowmaster Am Thunder cat-back it replaced. The fit & finish is top notch! No more banging against the floor boards or frame under hard acceleration! If you want really loud all the time go with LM1 & an x-pipe.


      Year: 1998 Submodel: GT Orlando, FL

      Helpful (7)

    • 4/5

      June 26, 2009

      98 Cobra SLP x-pipe with cats + SLP LM2

      Firstly, this is a great kit, if you have expericence u will agree. Most people want to know the sound level to expect with the LM2 compared to the stock exhaust or the LM1. I have the SLP catted X-pipe(get this first, its awesome) and minor intake ect work done. The LM2 i sdefinitely not overly loud. I removed a Flowmaster cat-back to install this LM2. Its quieter than the Flowmaster except on hard acceleration its louder and sounds better, its deep. I wish it overall was a little louder tho, at idle or just a cruise speed, even over 80mph, you can barely hear the car running at all. It does sound good on acceleration, if you want LOUD i expect the LM1 shoud get you there. From the videos ive seen and the fact that the LM1s are just resonators, the volume level is gonna be to the max and too loud for some. Im gonna buy the LM1s next month and switch them out for fun.

      Jayme Mckinney

      Year: 1998 Submodel: Cobra

      Helpful (8)

    • 5/5

      July 02, 2008

      Very Nice!

      The SLP Loudmouth 2 exhaust sounds awesome! This is the first and only exhaust system I will ever buy. This is truly a great system to buy.

      Dustin A.

      Helpful (6)

    • 5/5

      April 16, 2008

      Almost Perfect

      First of all, I\'d like to thank American Muscle for amazing service and great, fast shipping. Got it to me a day earlier than expected. Thank you AM! The SLP Loudmouth 2 kit is simply put: GREAT. The fit and finish is spot on. Everything you need for a great and easy installation is in the box. This was the 2nd time I have ever installed exhaust on one of my mustangs and I did it by myself with basic tools in under 2 hours. Great job SLP! This kit also sounds fantastic. Loud without being too loud. Great smooth, deep tone without any drone or being raspy. Somewhat like Magnapacks but more smooth. In my opinion, the perfect mustang sound. Thank you SLP!


      Helpful (6)

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