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SLP Loudmouth Cat-Back Exhaust (86-93 LX; 93 Cobra)

Market Price $519.95 You Save 4% ($20.00)
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  • Item 23021

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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 1986-1993 5.0L LX & 1993 SVT Cobra
    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 1986 to 1993 5.0 LX and 1993 SVT Cobra Mustangs to give it a rich, throaty sound.

    Fitment: 1986 1987 1988 1989 1990 1991 1992 1993 Details

    MPN# M31015

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    Hardware included:
    • 8 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: 1986-1993 LX and 1993 SVT Cobra Mustangs
    Will it fit my Mustang?

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        Questions & Answers (12)

        5 Top Rated Questions

        Would this clear a MM pan hard bar?

        • The SLP Loudmouth Cat-Back Exhaust will clear a Maximum Motorsports Pan Hard Bar.

        Helpful (1)

        Would this fit a 1990 gt 5.0 convertible

        • This will not fit GT models.

        Helpful (0)

        can I switch the tailpipe/tip out with the oem ?

        • Yes, you would be able to switch out exhaust tip with the OEM one.

        Helpful (0)

        Will this exhaust give my car the loud old school muscle car sound I'm looking for?

        • The SLP Loudmouth Cat-Back Exhaust will have a very aggressive, racey sound, more akin to NASCAR than an old Muscle Car sound.

        Helpful (0)

        Will this product work with the saleen rear valance

        • The 3.5" tip of the SLP Loudmouth Cat-Back Exhaust will not properly clear the Saleen rear valance.

        Helpful (0)
        Post Your Question
        7 More Questions
        Would this fit my 1985 mustang gt 1 answer
        will this system work for a 89 lx convertible with the 5.0? 1 answer
        Will this fit my 1988 5.0 LX convertible? 1 answer
        Will this fit a 91 5.0 gt convertible? 1 answer
        Will this fit on a 1985 5.0 GT convertible? 1 answer
        Will this exhaust system work with a 2001 Mustang that has been 5.0 swapped? 1 answer
        Does this part fit a 1993 lx 4 cylinder mustang? 1 answer

          Customer Reviews (22) Write a Review

          Overall Rating 4.8

          out of 5 stars

          Installation Time:Afternoon

          Installation Cost:$250-$500

          • Loudness / Volume 4.727273 4.7
          • Exhaust Note 4.818182 4.8
          • Fit & Finish 4.727273 4.7
          • Bang For Your Buck 4.818182 4.8

          • 4/5

            Installation Time: Afternoon

            May 04, 2019


            Put these on my 1992 notchback and all I gotta say is if you wana wake up your stang and love the loud bold sound than these are what you need.


            Year: 1992 Submodel: LX

            Helpful (1)

          • 5/5

            Installation Time: Afternoon

            September 25, 2018

            89 gt SLP LOUD MOUTH EXHAUST

            Fit great. Sounds really good with off road X pipe. Would recommend this for anyone replacing their exhaust system. Loud but not too loud.


            Year: 1989 Submodel: GT

            Helpful (2)

          • 5/5

            Installation Time: Afternoon

            July 13, 2018


            Love the sound that comes with the SLP Loudmouth cat-back. Installation was fairly simple and strait forward. My only complaint is that there was some rough cutting on the pipes that left some metal sticking off of the edges. Other than that they were perfect


            Year: 1989 Submodel: LX

            Helpful (2)

          • 4/5

            December 26, 2017

            Great sound

            This sounds great. And is quality made. Only received 4 stars because the clamps are a pain.


            Year: 1991 Submodel: LX

            Helpful (4)

          • 5/5

            Installation Time: Less than 1 Hour

            December 18, 2017

            Slp loud mouth

            Great sound!!! Like it sounds more aggressive. I put it together with o/r x-pipe and i got to say i break more necks out on the street, overall i love the deep tone it has. Not even gassing it and its loud and once i put the petal to the floor its just an amazing sound.


            Year: 1990 Submodel: LX

            Helpful (5)

          • 5/5

            August 09, 2017


            I haven't put this exhaust on yet it's going to be awhile I'm in the process of building this car motor first so why put it on till I'm done other than that it looks pretty sweet can't wait till it's on to hear the roar THANKS AMERICAN MUSCLE


            Year: 1989 Submodel: Other

            Helpful (4)

          • 5/5

            Installation Time: Afternoon

            January 28, 2017

            These sound great!

            Not bad at lower RPM but once the revs come up these loudmouths live up to the name. Is raspier then most. More higher pitched cackle but with a nice deep tone at idle.


            Year: 1991 Submodel: LX

            Helpful (8)

          • 5/5

            Installation Time: Afternoon

            January 17, 2017

            '86 GT SLP Loudmouth

            I Installed this SLP loudmouth catback on my 1986 mustang gt to replace a very poorly installed flowmaster exhaust system. The flowmaster super 40s sounded ok if they weren't rotted. This just blows them away though IMHO. It's a stock 5.0 with factory manifolds and H pipe and I think the cats are gutted. It does drone some around 2000-2500 rpms but it's not nearly as bad as straight pipes. Haven't gotten pulled over yet in NYS with them. Love the look as well. Definitely recommend to anyone looking for a much louder more full exhaust note. I thought the super 40s sounded a bit tinny then again they where in bad shape. Can't wait to get some Lt headers and a new mid pipe.


            Year: 1986 Submodel: Other

            Helpful (8)

          • 5/5

            Installation Time: Afternoon

            December 26, 2016

            Best exhaust I could've chosen.

            Loudmouths are exactly how their name describes them. They are VERY loud, and still give you a great tone. They fit on perfectly, everything took about 3 hours to do in a garage on jackstands. If you have a lift, this project should go much shorter, probably about 2 or so hours. We ran into some trouble at the flanges not because of the SLP's but because the stock H-pipe flange bolts were seized and snapped when we tried to remove them. After we got new bolts, it was a breeze! The resonators look gorgeous under the car and the tailpipes run pretty flush with the rear bumper. Overall, the fit and finish is great! If I had to do it over, I'd definitely still get this kit.


            Year: 1992 Submodel: LX

            Helpful (7)

          • 5/5

            July 27, 2016

            Sounds awsome!!

            This kit gives your 5.0 the true mustang growl! I've had flowmasters, magnaflows, and pypes systems in the past and this is hands down my favorite! Has some drone in the cabin but its not unbareable, well worth the money from the stainless hardware to the polished tips it's top notch!


            Year: 1989 Submodel: Other

            Helpful (5)

          • 5/5

            Installation Time: Less than 1 Hour

            June 10, 2016

            Sound, installation, and adjustment all great

            With the multiple clamps and separate pieces installation and adjustment is a breeze. This went on my buddy's fox lx easily and alowed the engine sound to continue to the rear of the car without any real sound disturbance from the mufflers.


            Year: 1995 Submodel: Cobra

            Helpful (6)

          • 5/5

            Installation Time: Shop Install

            Installation Cost: $250-$500

            November 23, 2012

            Insane sound and very loud

            I actually have an '01 V6 model, and I paired this SLP Loudmouth system with MAC long tube headers and a MAC off road H pipe. I know that sounds odd but I was told by MAC that an '86-'93 LX 5.0 cat back was the kit to use for their headers (by the way, AM needs to start selling MAC products). So my first thought for a cat back to finish off the exhaust job was an SLP Loudmouth kit. Needless to say, this was a great combination in every way. A friend did the install in his shop and everything did indeed hook together with no problems. I wasn't sure about the look of the double walled tips that this kit uses but they have quickly grown on me. Upon startup I couldn't believe how loud this kit is. If you want to really hear your Mustang, regardless of engine, the SLP Loudmouth is what you need to have, period. It's very loud at anything above 2500 rpm, with a noticeable, but not too loud, of a drone at cruising speeds on the highway. But anytime you want to turn some heads, this kit will make your Mustang one of if not the loudest cars on the road. Overall everything about this SLP kit is top notch. And as usual, Americanmuscle had the best price on this kit and it was shipped within 3 days time. Many thanks!


            Year: 2001 Submodel: V6 Fairfield, IL

            Helpful (5)

          • 5/5

            June 10, 2011

            Let it rumble

            Great set of pipes Took alot of adjusting after I had it on buy I'm a picky person I teamed the pipes up with BBK long headers and X-pipe. Great combo


            Year: 1991 Submodel: Other

            Helpful (8)

          • 5/5

            March 12, 2011

            slp loudmouth exhaust

            american muscle's fast delivery allowed me to have the exhaust to my house and installed in 3 days. Fit perfect and the sound is above and beyond my expectations. Wouldn't put any other system on after hearing this one. Awesome!!!

            shawn witham

            Year: 1992 Submodel: Other

            Helpful (6)

          • 5/5

            January 16, 2011

            Best quality product I've used

            I put a set of SLP's on my wife's 96 Cobra. I liked it so much, I put a set on my 93 LX. A friend liked that so much, I put a set on his 88 Saleen. Loudmouths have a deep, aggressive tone that sounds like no other cat-back available. The quality of the product is exceptional and fits better than any other I've ever worked with. To those that have complained about the tips being too short and showing "ugly pipe", these pipes are stainless steel. Hit them with a little metal polish before you install them and they look great.


            Year: 1996 Submodel: Cobra

            Helpful (9)

          • 4/5

            July 19, 2009

            great sound bad looks

            slp loudmouth exhaust of my mustang is great. the sound has a great rumble at idle, very quite at highway speeds, nice strong sound at wide open throttle. only problem i have with the exhaust is the way it looks from the side. the tips are the only thing that is chrome and they do not extend back far enough to the rear tires there for you can see some very ugly pipe from behind the car exhaust looks good with the big tips.


            Helpful (9)

          • 5/5

            January 21, 2009

            93 LX Hatch

            Just installed this kit today and love it! Definitely a different sound and really aggressive when you get on it. Pretty mellow when you are just driving around too.


            Year: 1993

            Helpful (9)

          • 4/5

            August 27, 2008

            89 notch

            Nice rumble at idle and aggressive when the pedals on the floor. Exhaust tips look good from behind, but not happy with how they look on the side. Would be better if pipe was polish from rear axle to tips.


            Year: 1989

            Helpful (5)

          • 5/5

            July 11, 2008

            1990 GT Convertible

            Definitely the best sounding Mustang exhaust to anger your neighbors!


            Year: 1990 Submodel: GT

            Helpful (10)

          • 5/5

            January 31, 2008

            88 Notchback 5.0

            Awesome, nice deep, aggressive tone. Perfect for ticking the law off! Haha


            Year: 1988

            Helpful (8)

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