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Flowmaster Outlaw Series Axle-Back Exhaust (15-18 EcoBoost)

Market Price $499.99 You Save 16% ($80.00)
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$419.99

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  • Item 525581A
  • MPN# 817713

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    Features, Videos & Details

    • Super Aggressive Flowmaster Outlaw Sound
    • Durable 409 Stainless Steel Construction
    • 2.5" Mandrel-Bent Tubing
    • 4" Polished Stainless Steel Tips
    • Includes Two Flowmaster Outlaw Mufflers
    • Fits 2015-2018 EcoBoost Mustangs

    Review & Installation Video

    Justin: What's up, everybody? Justin with americanmuscle.com. I have Angelo in here with me today. He brought his brand new 2015 EcoBoost. We understand this isn't your first Mustang. Obviously, you have a little history with the Mustang. Tell us a little bit about it. Angelo: Yeah. Before the 2015, I had 2 Mustangs. I had a 2008 GT California Special. That was supercharged, Paxton NOVI 2200, Ford racing hot rod cams, and some Kooks long tubes. Justin: Very cool. Angelo: I also had a 2014 GT Track Pack, basic bolt-ons, nothing too crazy. Justin: How are you enjoying the new EcoBoost? Angelo: Definitely can't complain. The gas mileage has been awesome and it still has all the fun. It's an incredibly balanced car to have some fun on the street. Justin: That's what I like to talk about. We understand you like to do some events. I know you were talking to me about that. You love doing some solo stuff, some autocrossing. You've got to be loving the IRS. Angelo: It's a much better package out of the box than I expected, to be completely honest. Justin: Okay. As always, there's always room to improve. That's why you're here with us today. What are you looking for out of the car? Angelo: I'm looking to improve the ride height a little bit and stiffen it. Get a little of that brake dive out of there. Improve the body roll. Have it a little more predictable while I'm having some fun with it. Justin: It's probably a little quiet I'd imagine, right? We heard these stock EcoBoosts before. Angelo: Yeah. Justin: It's a fine line. You don't want to go too loud with the four cylinder, but I think we have something for you that might help you out. Angelo: Awesome. Justin: We definitely have something for the suspension that you helped us pick out. We're going to get you out of here. We're going to get to work on it. Then, we'll bring you back in and see what you think. All right, guys. We're getting started here with Angelo's EcoBoost. Angelo is a self proclaimed road racer. He's done some autocross stuff in the past. Therefore, he's very familiar with Eibach, as most of us are. He really wanted to go with the pro-kit here. The pro-kit is the milder of the two options from Eibach, the other one being the sport line which do drop the car a little more. The pro-kit is going to drop his Eco boost just over an inch up front and an inch in the rear, getting rid of that wheel gap, lowering the center of gravity, and really helping his cornering in the process. Guys, with any spring install, of course, you're going to need your spring compressor here. We've got ourselves a nice one. It makes the job a heck of a lot easier. Trust me. We already got the other side installed, so we're just going to finish up here with the driver side and then move to the rear. With the car still up in the air, we have a couple more performance parts we're going to do. Let's do the exhaust first. Guys, just wrapping up the axle-back here with Angelo's EcoBoost. He wanted the Flowmaster Outlaw series axle-back for now. Definitely looking for a little bit more performance. A little bit more sound is going to be a given here with this exhaust. It is an axle-back with the 2015, so you do have to cut. As long as you make the right measurements and make a good cut with the Sawzall, you should have it up and in no problem in about an hour I'd say. All right, guys, I'm a fan of starting with the hardest stuff first, the springs in that case, and then working towards the easier stuff, which in this case, is this brand new Airaid cold air intake that Angelo's getting for his EcoBoost. The Airaid is a great product. With these 2015 EcoBoosts, it's a no tune required intake. It shouldn't take any longer than 30 minutes to throw on. We'll get it on, get Angelo in here, and see what he thinks. What do you think of the ride height? Angelo: That's exactly what I was hoping for. Justin: Yeah? Nailed it, huh? Angelo: The ride height is perfect. It has just a little bit of rake. The front's a little bit lower. Got rid of that lifted front end it had from the factory. Justin: Absolutely. I love the pro-kit, too, because of that. A lot of the springs level it out. The pro-kit drops a little bit more in the front as you pointed out. I think it really is a perfect stance. Angelo: Definitely. Justin: Well, Angelo, before we set you loose on the roads, man, obviously we've got the car all go pro up here. Why don't you fire this thing up and let's hear how that Flowmaster sounds. Angelo: Yeah, let's do it. Justin: Okay, nice. Nice, man. Angelo: Definitely more refined than I was expecting for the EcoBoost. Justin: I'm with you, man. It's definitely not obnoxious whatsoever. It actually sounds really good. You get a little turbo noise through there. Angelo: Yeah. Justin: You happy with it? Angelo: Absolutely, that's exactly what I was hoping for. Justin: Very cool. Let's get you out on the roads here. You can tear it up and let us know what you think. Angelo: All right. Let's see how this exhaust sounds here. Oh yeah, nice little crackle out the end. That sounds perfect. Definitely a huge step up from the stock muffler, but still refined. Springs are definitely comfortable. Not too stiff, but definitely has a lot more control. Alot less brake dive. Springs feel perfect on the corners. Much more predictable. That blow off valve is a lot louder than I expected. The intake definitely helped out with the throttle response. It seems like I barely need to give it gas for that turbo to respond. It's crazy how much you can get out of three simple mods. Justin: Angelo, you just got done blasting around in the EcoBoost with all the mods. What do you think so far, man? Angelo: I think it's exactly what I was hoping for out of this package. It's got a balanced suspension. It's got a nice note out of the exhaust. And, I can hear the turbo on a little of that diverter valve. Justin: There you go, man. Thanks so much for bring the car by, brother. Angelo: Thank you. Justin: We really appreciate it. I know you're not done with this thing, so maybe as you'll want to do some more mods, you'll bring it through. Angelo: Sounds good. Justin: All right, man. Thanks for watching guys, and for all things Mustang, keep it right here at americanmuscle.com.

    Super Aggressive Flowmaster Sound. Give your EcoBoost powered Mustang that unmistakable Flowmaster sound with the Outlaw Series Axle-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.

    Stainless Steel Construction. Constructed from durable 2.5" 16 gauge 409 stainless steel tubing for it's corrosion resistant properties, the Flowmaster Outlaw Axle-Back features (2) 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.

    Cut & Clamp Installation. The installation of this Axle-Back Exhaust requires cutting and removing the stock muffler assemblies, and clamping the new muffler assemblies in place. Clamps and instructions are provided.

    Application. This Flowmaster Outlaw Series Axle-Back exhaust system is designed to fit the 2015-2018 EcoBoost Mustangs for both great looks and great sound.

    Fitment: 2015 2016 2017 2018 Details

    What's in the Box
    • (2) Muffler Assemblies
    Installation Info
    Tech Specs
    Axle-Back Exhaust Specifications
    Piping Material: 409 Stainless Steel Tip Material : Polished Stainless Steel
    Piping Size: 2.5" Tip Size: 4.0"
    Muffler Type: Straight-through Fitment: 2015-2017 EcoBoost
    Will it fit my Mustang?

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    48 Questions / 94 Answers

    Ask a Question

    Does installing the Flowmaster Outlaw Series Axle-Back Exhaust on my 2017 Mustang eccoboost affect the new vehicle warranty from FORD?

    WilliamC

    • Hello, Ford explained to me that the only way and after market part would void the warranty is it poorly malfunctioning.

      SpencerM

    Helpful (3)

    I live in California. If i put this on, will i still pass smog? This is probably the only reason holding me back. I have a 2017 v6 mustang.

    Daniel

    • The Flowmaster axle backs will pass smog testing however you will want to check your local laws on noise restraints to be safe.

      Ricky36

    Helpful (3)

    I have the convertible version of the 2015 Mustang Ecoboost Premium. With this axle-back fit?

    JPS04001

    • The Flowmaster Outlaw Series Axle-Back Exhaust is designed to fit both coupe and convertible ecoboost Mustangs.

      Rob D

    Helpful (2)

    is this product legal in the Rio Grande Valley ,Texas

    reys

    • Unfortunately, we are not familiar with the local laws and regulations in your city. Please contact your local Department of Transportation, and/or Law Enforcement Agency.

      VincentV

    Helpful (1)

    Is this system compatible with the Flowmaster Scavenger series Y-pipe?

    Josiah

    • The Flowmaster Scavenger Series Cut and Clamp Resonator Delete Y-Pipe, Item 389694 is compatible with these axle-backs. http://www.americanmuscle.com/flowmaster-y-pipe-2015gt.html

      AMJEFF

    Helpful (1)

    Everything comes as shown in the photo?

    RaynardT

    • These Flowmaster Outlaw Series Axle-Back Exhaust include the muffler assemblies and the clamps shown in the product photos.

      AMJEFF

    Helpful (1)

    People Who Bought This Item Also Bought

    Customer Reviews (100+) Write a Review

    Overall Rating 4.7

    out of 5 stars

    Installation Time:Afternoon

    Installation Cost:$100-$250

    • Loudness / Volume 4.369697 4.4
    • Exhaust Note 4.636364 4.6
    • Fit & Finish 4.836364 4.8
    • Bang For Your Buck 4.745454 4.7



    • 4/5

      Installation Time: Less than 1 Hour

      June 17, 2018

      Decent not obnoxious

      The exhaust sounds great but the videos I’ve seen I expected something louder, but I am glad that it’s not. It sounds great and it’s really growing on me. It’s a good combination of great sounding and not being obnoxious. I would recommend these. I had a muffler shop install these and they were done in like 45 min but the clamps it came with were too big or something so they had to tack weld it into place.

      Renny

      Year: 2016 Submodel: EcoBoost

      Helpful (0)

    • 5/5

      June 09, 2018

      Just right

      I got this as one of my first mods. I'm pleased with the product. It has a nice aggressive tone, but is not as loud as a lot of the videos suggest. It quites down a bit after idle. The car is slightly more responsive. Definitely worth the money if you don't want to get a cat back right away; and want to put towards other mods. Recently had an AEM CAI installed and it sounds even better. Will probably get a y pipe/ resonator delete in the future.

      DAllen

      Year: 2016 Submodel: EcoBoost

      Helpful (1)

    • 4/5

      Installation Time: Less than 1 Hour

      June 05, 2018

      Exhaust

      One of the best purchases so far. The exhaust gives a very nice mean sound on my ecoboost mustang. Highly recommend it.

      MarkA

      Year: 2015 Submodel: EcoBoost

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      June 02, 2018

      Great Sound

      Just measured cut pipe. Easy bolt on. Sounds amazing. Not too load. just perfect.

      Talib

      Year: 2018 Submodel: EcoBoost

      Helpful (1)

    • 3/5

      May 29, 2018

      Didnt work for me

      I can say everything is good. This is the first mod I did and had to cut the stock one and fit this. After a little while the car seemed a lot slower. I removed this and welded back the old ones. Now for atleast 2 years I have been having trouble to get back the same throttle response and all. I liked the tone but not sure what went wrong or just my perspective, didn't like the pickup.

      sudheerC

      Year: 2015 Submodel: EcoBoost

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      May 26, 2018

      Amazing!

      If you want to wake up your ecoboost these will for sure turn it into a ecoBEAST

      JustinR

      Year: 2015 Submodel: EcoBoost

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      May 24, 2018

      Worth the money

      Well worth the money its everything I expected plus some. Gave my EcoBoost the sound I was looking for.

      BrianP

      Year: 2017 Submodel: EcoBoost

      Helpful (1)

    • 4/5

      Installation Time: Less than 1 Hour

      May 22, 2018

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      Like it a lot

      Sounds very nice. Loud but not too loud. Exhaust note could be a bit better.

      FrankM

      Year: 2015 Submodel: V6

      Helpful (1)

    • 4/5

      Installation Time: Afternoon

      May 19, 2018

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      Flowmaster

      For the price you can’t really beat the benefits from this axleback. It has a bit of a drone. By any means it does not make you sound like a v8 but when you hit it, it is a head turner. Noticeable gain in horsepower right after install. Even pulled with a 2016 hemi dogde charger and gave him a run for his money. Happy with the purchase!

      EddieH

      Year: 2017 Submodel: V6

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      May 15, 2018

      Sound Great

      These were a great buy and really brought my Eco to life. They sound much better than they do in any videos online. For the price they can't be beat! 5 stars.

      MustangFrank

      Year: 2015 Submodel: EcoBoost

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      May 13, 2018

      wow

      I put these on my wifes 2018 eco boost today and we are quite surprised with the sound. A little louder than i thought but nice sure notice when you get the rpms up.

      JeffD

      Year: 2018 Submodel: EcoBoost

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      May 13, 2018

      Great sound quality

      Sound is great just enough tone a a little crackle on deceleration paired with resonator delete scavenger y pipe

      Riley00Coyote

      Year: 2018 Submodel: EcoBoost

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      May 10, 2018

      Flowmaster outlaw

      It has a nice and deep sound, but it’s really quite when the car is running on low rev, only gets loud when u want it to be, very happy with it

      TommyX

      Year: 2017 Submodel: EcoBoost

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      May 09, 2018

      some drone, decent tone

      You can defiantly tell the car is 4cyl but sounds good. some drone around 2k but not bad. My wife actually likes the sound more than I do.

      MatthewB

      Year: 2016 Submodel: EcoBoost

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      May 01, 2018

      Awesome sound

      Love the sound . Definitely feels like a sports car now . Great deal $409 dollars.

      MarvinV

      Year: 2015 Submodel: EcoBoost

      Helpful (2)

    • 3/5

      Installation Time: Less than 1 Hour

      May 01, 2018

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      Too much drone

      Nice fit and finish.. sounds deep and loud .. cold start is great.. but I hate the drone at 120kmph..

      AJ

      Year: 2017 Submodel: V6

      Helpful (2)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $100-$250

      April 27, 2018

      Nice sound

      Not too loud but loud enough and aggressive when in the throttle

      KedrickJ

      Year: 2018 Submodel: EcoBoost

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      April 21, 2018

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      Everything I was looking for...

      When purchasing the product I wanted to get something that I can turn heads when I was driving by and something to rev at the lights. This has put a smile on my face instantly!! Happy I purchased the product. If your thinking about it don’t think any longer great price and sounds awesome!!

      KourtneyG

      Year: 2015 Submodel: V6

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      April 20, 2018

      Review from Flowmaster Outlaw Series Axle-Back Exhaust (15-17 V6)

      Best sound

      I live these mufflers and they always catch everyone's attention and turn heads! Easy to install and sounds so good with the Flowmaster X-pipe!

      AveryP

      Year: 2017 Submodel: V6

      Helpful (2)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $100-$250

      April 11, 2018

      Sounds so much better!

      I love my 15' Ecoboost. But the sound was just so boring. After adding the Outlaw series axle-back, my car sounds great!! Great bass tone, with some nice crackle during shifts. The shop installing it kept telling me that I'd be back to delete the resonator. But once they had it on, they changed their minds. This week I added the Rush CAI, it sounds even better!

      12ozRuss

      Year: 2015 Submodel: EcoBoost

      Helpful (2)

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