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Flowmaster Outlaw Cat-Back Exhaust w/ X-Pipe - Stainless Steel (13-14 GT)

AmericanMuscle no longer carries the Flowmaster Outlaw Cat-Back Exhaust w/ X-Pipe - Stainless Steel (13-14 GT). Please check out 2010-2014 Mustang Cat-Back Exhaust for an updated selection.

Features, Video & Details

  • Super Aggressive Flowmaster Outlaw Sound
  • 409 Stainless Steel Construction
  • 3" Mandrel-Bent Tubing
  • 4" Polished Stainless Steel Tips
  • Includes Scavenger X-Pipe and Two Flowmaster Outlaw Mufflers
  • Fits 2013-2014 GT

Review & Installation Video

Review & Install Video

Hi I'm Justin with AmericanMuscle.com, and I'm going to be breaking down the Flowmaster Stainless steel Outlaw Catback exhaust system fitting all 2013 Mustang GTs. This system gets its name from the two, race oriented, straight through design Outlaw series mufflers, which are going to be far more aggressive than Flowmaster's other street offerings, such as the super 44 or the delta for instance. In fact, Flowmaster claims that this system, is the most aggressive system they produce for the Coyote Mustangs. Taking a closer look at the entire system, you will notice that Flowmaster chose to go with a quality 409 grade stainless steel throughout, including the 3" mandrel bent tubing, through those Outlaw series mufflers, all exiting out these brightly polished 4" tips. Since this is a Catback, you can expect a slightly more involved install, that should take you about 2 hours from start to finish when it's all said and done. Now let's hear how the Flowmaster Outlaw series sounds compared to our factory exhaust.

Super Aggressive Flowmaster Sound. Give your coyote powered Mustang that unmistakable Flowmaster sound with the Outlaw Series Cat-Back exhaust system from AmericanMuscle. This system improves exhaust flow using Flowmaster's race-oriented style Outlaw mufflers for that super, aggressive exhaust note your high powered Pony deserves.

Race Car Growl. The included Scavenger X-Pipe not only helps increase power, but it also adds a loud raspy, race car growl to the sound of your exhaust with its modern "X" crossover pipe design.

Reuses Stock Cats. The included Flowmaster Scavenger X-Pipe bolts up directly behind the factory catalytic converters with no cutting required saving you time and money. By reusing your stock catalytic converters, you ensure that your Mustang is smog-legal.

Stainless Steel Construction. Constructed from durable 3" diameter 16 gauge 409 stainless steel tubing for it's corrosion resistant properties the Flowmaster Outlaw Cat-Back features two race-oriented mufflers with massive 4.0" diameter polished stainless steel tips for impressive muscle car looks and sound. As an added bonus the tips are embossed with the "Flowmaster" logo for true custom styling.

Application. This Flowmaster Outlaw Series Stainless Steel Cat-Back exhaust system is designed to fit the 2013-2014 5.0L coyote Powered GT Mustang equipped with either aftermarket shorty headers or the factory manifolds. Does not fit Shelby GT500 models.

Fitment: 2013 2014 Details

MPN# 817590

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

What's in the Box
  • (1) Right muffler assembly
  • (1) Left muffler assembly
  • (1) Scavenger X pipe assembly
  • (1) Right intermediate pipe
  • (1) Left intermediate pipe
  • (4) Band clamps
  • (2) Hanger keepers
Installation Info
Tech Specs
Axle-Back Exhaust Specifications
Piping Material: 409 Stainless Steel Tip Material : Polished Stainless Steel
Piping Size: 3" Tip Size: 4.0"
Muffler Type: Straight-through Fitment: 2013-2014 GT
Will it fit my Mustang?

    Customer Photos (14) Submit Your Photo

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      Questions & Answers (27)

      5 Top Rated Questions

      is it possible to weld new flowmaster tips onto the outlaw catback? i want to get dual tips

      • While it is possible to weld new Flowmaster tips to the end of the Outlaw catback, you will be modifying the sound that is produced when going from a dual tip to a quad tip setup. Not to mention that you will need a new GT500 rear valance to accommodate the new tips as the stock rear valance is too small to fit the quad tip exit on it.

      Helpful (2)

      Will this set up work with bbk long tube headers and off road x-pipe?

      • This set up will work however you will need to remove the X-pipe that comes with this kit to work on the long tubes and short X-pipe.

      Helpful (1)

      Two questions. 1 - If using the Flowmaster Outlaw Cat-Back w/X-Pipe does the car have to be tuned afterwards? 2 - If not, if I would do BBK shorty headers and the Outlaw Cat-Back exhaust does the care have to be tuned afterwards?

      • Just this cat-back would not require a retune no. When adding the shorty headers a tune is highly recommendedbut still not needed. 

      Helpful (1)

      Catback vs. Axleback Is there a noticeable difference in exhaust tone and/or performance between the axleback outlaws and the catback system?

      • There will be a subtle difference in tone. It depends on how keen your ear is. Either will be an improvement over the stock exhaust. Be prepared, the exhaust will be louder overstock, but will sound better which is probably what you want, but your neighbors may not. I would recommend checking out other Mustangs to see what different setups sound like. The exhaust tone is a personal preference. Everyone has a different idea of what they think is the right sound. As far as performance, there may be a slight increase in HP due to less exhaust restriction, but either does not require a tune. Most of the time the better exhaust sound (when you have your foot into it) makes you perceive that you have more power. You would feel the power increase with a set of long tube headers, but probably not too much with the aftermarket catbacks or axle backs. Hope this helps…. 2fast08

      Helpful (1) Show 2 more answers

      Does this product have issues with passing emimission inspections? Have trouble passing due to o2 sensors and catalytic sensors not setting.

      • This item will pass emissions since it does not affect the cats at all.

      Helpful (0)
      Post Your Question
      10 More Questions
      How much weight would I be saving from switching to the Flowmaster cat-back system. 1 answer
      what fitment issues would this have with a 2012 1 answer
      How does this compare to a corsa extreme catback? 1 answer
      Does this kit require buying extra exhaust clamps? Or is the supplied amount enough? If so can you provide a part number for the clamps I’ll need 1 answer
      will I be able to run BBK long tube headers with this exhaust ? 1 answer
      Is it possible to get everything listed here except the X-pipe? I want to run an H pipe with this. 1 answer
      I am wanting to do a full exhaust with Long Tube Headers. Do any of the Long Tube Headers come close to being able to connect to the Flowmaster Cat-Back? I know most likely some modification would be needed to bridge the difference between the Cat-Back and the LTH. 1 answer
      Instead of receiving the scavenger x pipe can y'all replace it with an off road h pipe? 1 answer
      I want to buy headers for my car, but would this cat back fit the kooks headers if i buy the catted x pipe and replace it for the scavenger x pipe? 1 answer
      is there a outlaw series that will fit a 2012 boss 302 1 answer

        Customer Reviews (68) Write a Review

        Overall Rating 4.8

        out of 5 stars

        Installation Time:Full Day

        Installation Cost:$100-$250

        • Loudness / Volume 4.923077 4.9
        • Exhaust Note 4.907692 4.9
        • Fit & Finish 4.569231 4.6
        • Bang For Your Buck 4.878788 4.9



        • 5/5

          Installation Time: Shop Install

          Installation Cost: $100-$250

          March 08, 2019

          WOW!!!!

          The other reviews on this are correct. It is LOUD!!! I'm very happy though the shop guy was not. the exhaust didn't go on very easy but in the end it looked fine. All in all I'm a very happy customer.

          Cullen

          Year: 2014 Submodel: GT

          Helpful (0)

        • 4/5

          Installation Time: Afternoon

          January 11, 2019

          Amazing sound

          for the cost i get amazing sound, cant be any more happy with the results . only to half a day due to not having a lift, is doable with jacks just takes longer.

          MarkM

          Year: 2014 Submodel: GT

          Helpful (2)

        • 5/5

          Installation Time: Shop Install

          Installation Cost: $100-$250

          September 20, 2018

          Great sound

          Very loud but it has an awesome tone. Frees up a lot of exhaust gases and you can feel the car drive smoother

          14sleep

          Year: 2014 Submodel: GT

          Helpful (2)

        • 5/5

          Installation Time: Shop Install

          Installation Cost: 0-$100

          September 18, 2018

          Flystang II

          My 2013 GT had to be woken up, I wasn't feeling the stock Muffler. The Flowmaster Outlaw catback exhaust sounds like a Beast I'm very satisfied

          DJFLY

          Year: 2013 Submodel: GT

          Helpful (2)

        • 5/5

          September 16, 2018

          Great sound!!

          This exhaust provided the boost that I wanted and it has a fantastic deep sound! I highly recommend this.

          JonathanP

          Year: 2013 Submodel: GT

          Helpful (2)

        • 5/5

          Installation Time: Shop Install

          July 15, 2018

          Great Recommendation

          Ok so I want to give my honest well put review to help out everyone deciding to buy an aftermarket exhaust. I have been to a lot of car shows/meets and I have heard just about every brand/model of exhaust systems that the 2013-14 GT's have to offer. This is by far the best sounding exhaust system on the market. This is just as loud as the Borla ATAKs and the Outlaws are more deep and give your 5.0 a very NASCAR sounding trait. One thing is for sure, make sure you either do it yourself or have a high quality shop do it for you. The reason I say this is because if it is done wrong, your hangers and clamps will be damaged and the exhaust system will squeak due to installing it wrong and overtime it will stick to your bumper because of the hanger/clamp getting damaged from careless installment. I know because the shop I took it to damaged it without telling me. I also installed the MBRP H-pipe and took off the X-pipe after a year and had a shop install it because they welded it needed to be welded. Future plans are MBRP long tube headers. BTW this exhaust system drones a lot, but after I installed the MBRP H-pipe, it went down quite a bit and to be honest I got use to it and it doesn't bother me. So here is what I recommend: -If you are looking to get the best sounding exhaust system on the market: Buy the Outlaws -If you are looking to get something that sounds better than stock that doesn't drone: buy something else like Borla

          NicholasL

          Year: 2014 Submodel: GT

          Helpful (5)

        • 5/5

          Installation Time: Afternoon

          July 14, 2018

          Perfect!!

          It was definitely worth every dollar. Took exactly 2 hours to install but 45 mins of that install was to make it even and have everything perfectly set which was difficult but hey that’s how life is. I definitely recommend the drone isn’t crazy especially if you play some music. The sound is LOUD. Can’t explain how happy I am.

          JamesM

          Year: 2014 Submodel: GT

          Helpful (2)

        • 5/5

          Installation Time: Shop Install

          Installation Cost: $100-$250

          June 27, 2018

          Worth the money

          I was skeptical about spending $800 on an exhaust but looking back I'm glad I did. It sounds amazing, it’ll get the attention of everybody around you. If you want a really loud exhaust, no question this is it!

          TheRealDSummers

          Year: 2013 Submodel: GT

          Helpful (3)

        • 5/5

          Installation Time: Less than 1 Hour

          June 06, 2018

          Flowmaster outlaw Cat-Back

          Placed my order 3-4 days later it came Easy install sounds amazing looks awesome absolutely love it!

          JudW

          Year: 2013 Submodel: GT

          Helpful (4)

        • 5/5

          Installation Time: Afternoon

          May 30, 2018

          Great Echaust

          Very loud but smooth. Put a big smile in your face every time you hit the gas. Complicated to install but doable.

          VictorF

          Year: 2014 Submodel: GT

          Helpful (3)

        • 5/5

          Installation Time: Afternoon

          May 06, 2018

          Deep growl, and a lot louder

          I was a little worried because a couple of the users said there was some drone. I didnt know what to expect. After the install and driving around a bit the drone is hardly noticeable. The install took a little longer than I expected because my brother and I did not use a lift and could not get enough clearance to take off the over Axel piping. We eventually decided to cut it and it came out with ease. If you are going to use floor jacks I recommend using a low profile jack that can raise up to at least 21". Other than that it came with everything i needed for the install. It sounds great and is very loud and a lot better than the Roush Axel back i had on. Definitely would recommend this to anyone looking to wake up the car!

          AdrianP

          Year: 2014 Submodel: GT

          Helpful (4)

        • 5/5

          Installation Time: Afternoon

          April 08, 2018

          Absolutely amazing

          This was an easy install. The only issue is that it doesn't mention that you require another clamp. The tone is deep and the overall performance and appearance is great.

          Will

          Year: 2014 Submodel: GT

          Helpful (5)

        • 5/5

          Installation Time: Afternoon

          February 28, 2018

          Best exhaust

          It’s not that raspy loud obnoxious coyote sound that we are used to it adds a beautiful deep tone on it that sounds like a muscle car

          KyleD

          Year: 2013 Submodel: GT

          Helpful (3)

        • 5/5

          Installation Time: Shop Install

          Installation Cost: $250-$500

          January 18, 2018

          Outlaws!

          It's a pricey exhaust no doubt, but believe me when I tell you that it more than pays for itself in performance gains but also in volume. Turns heads on the drop of a dime and I'm always getting compliments. A little drone at 2k on freeway but it's no big deal, I'm 100 satisfied with the purchase!

          Jeremiah5oh

          Year: 2014 Submodel: GT

          Helpful (4)

        • 4/5

          Installation Time: Less than 1 Hour

          January 11, 2018

          Flowmaster Outlaw

          If you want loud this is what you want. Install took 45 mins.

          TerianoC

          Year: 2014 Submodel: GT

          Helpful (5)

        • 5/5

          Installation Time: Less than 1 Hour

          December 10, 2017

          Loud!!!

          Great product much louder than expected. The audio clip doesnt do it justice, very agressive sound especially at full throttle. It does drone at highway speed not too terrible though, you can drown it out with the radio. I dont reccomend this if you daily drive on the highway though, it would probably get old real quick. But all in all very satiesfied with my purchase.

          RobertoG

          Year: 2014 Submodel: GT

          Helpful (4)

        • 5/5

          Installation Time: Less than 1 Hour

          October 11, 2017

          The world loves this Exhaust

          Almost daily I have people yell at me about how good this exhaust sounds rumbling down the street. Sure it wakes my neighbors up every morning at 5am but that's okay they're pricks. This setup on just a stock 5.0 sounds the absolute best in my opinion!

          CodyM

          Year: 2013 Submodel: GT

          Helpful (3)

        • 5/5

          Installation Time: Less than 1 Hour

          September 27, 2017

          Thunder

          The Flowmaster sounds exceptional , clearly loud, when you step off the gas it makes a beautiful thunder sound, I could not be anymore happier.

          AngelG

          Year: 2014 Submodel: GT

          Helpful (4)

        • 5/5

          Installation Time: Shop Install

          Installation Cost: $100-$250

          September 15, 2017

          So worth it!

          Cant even count how many ppl compliment how badass the car sounds

          ClaireM

          Year: 2013 Submodel: GT

          Helpful (3)

        • 5/5

          Installation Time: Afternoon

          September 01, 2017

          LOUDNESS IS 8 OUT OF 5 STARS

          If you are going to purchase this exhaust, really make sure you want the vehicle to ROAR, because it does just that. This sound WILL turn heads, including your neighbors. I already have all too much experience in waking them up, so if you live in a neighborhood where houses are tight fits, proceed with caution. 10/10 on the exhaust though, wouldn't change a thing about it. Flowmaster does it again!

          xJBiRDx

          Year: 2014 Submodel: GT

          Helpful (6)

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