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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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  • 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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    Questions & Answers (48)

    5 Top Rated Questions

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

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

    Helpful (4)

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

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

    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.

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

    Helpful (3)

    is this product legal in the Rio Grande Valley ,Texas

    • 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.

    Helpful (1)

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

    • 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

    Helpful (1)
    Post Your Question
    10 More Questions
    Everything comes as shown in the photo? 1 answer
    Does it require a computer tune? 1 answer
    Is it absolutely necessary to cut and bolt on or can I get away with not cutting at all? 1 answer
    I live in California and was wondering if this exhaust system is CARB certified. Would it pass smog check if I install it on my car? 1 answer
    Would I be able to install the stock exhaust system back 1 answer
    Does it come with new hangers 1 answer
    Will this product fit a 2014 v6? 1 answer
    How much does this product weigh? 1 answer
    My 2015 Mustang Ecoboost I currently straight piped. Would I still be able to install this Axle back? 1 answer
    Recently install a Borla s type catback on my 2017 v6 mustang. Was thinking about switching to this axle back so I could pair it with the x pipe. Will I be able to do this? Or do I have to get my stock pipe reinstalled for this. 1 answer

    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 4.33146 4.3
    • Exhaust Note 4.595506 4.6
    • Fit & Finish 4.83146 4.8
    • Bang For Your Buck 4.713483 4.7



    • 5/5

      Installation Time: Less than 1 Hour

      August 01, 2018

      Amazing

      They sound great easy to put on i love american muscle !!!

      FrankoS

      Year: 2017 Submodel: EcoBoost

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      July 28, 2018

      Best

      Worth every penny. Easy installation all you do is cut and place new flowmasters adjust and tighten clamps

      FranciscoT

      Year: 2015 Submodel: EcoBoost

      Helpful (0)

    • 5/5

      Installation Time: Afternoon

      July 28, 2018

      Makin' it flow

      Wow, what a difference to wake up the EcoBoost! Easy to install only takes a couple hours. Cant believe how much better it sounds and not droning at low rpm....also the tail pipes look great! Would highly recommend this easy mod if you want a little sound out of the rear end.

      RobertC

      Year: 2015 Submodel: EcoBoost

      Helpful (0)

    • 5/5

      Installation Time: Less than 1 Hour

      July 25, 2018

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

      Sounds great!!! But...

      Big difference in sounds a lot deeper and more muscle tone. But with that being said no it does not sound like a v8. It sounds great but a v6 will never sound like a v8. I do recommend this axel back though makes you v6 sound aggrisive and loud not so much were you will wake up the neighbors but enough we’re youll turn heads. Like I said sounds great! But! The Welding is terrible. It’s done very unprofessional. I wouldn’t be surprised if in a year or 2, it would get a leak in the exhaust. Flowmaster needs to work on that. But me and 2 of my friends knocked it out in little over an hour in the garage very easy install.

      jose

      Year: 2017 Submodel: V6

      Helpful (0)

    • 5/5

      July 22, 2018

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

      Great Immediate Upgrade

      As soon as I heard this I was in love and ready to complete my exhaust system. My neighbors don’t love it as much and that tells you all you need to know. Drone is a little heavy, but you get used to it.

      Landry

      Year: 2017 Submodel: V6

      Helpful (1)

    • 5/5

      July 13, 2018

      FlowMaster Outlaw on Ecoboost

      Good Sound, lightweight, easy install Fast Delivery

      Alberto

      Year: 2016 Submodel: EcoBoost

      Helpful (1)

    • 2/5

      Installation Time: Less than 1 Hour

      July 10, 2018

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

      well built, but way too much drone

      received the exhaust and installed fairly easily on my 2017 V6.....the problem is the drone is unbearable anywhere below 3000 RPM....which is all the time when driving in the city....I read reviews that said it wasnt that bad.....flatout liars...its absolutely atrocious...DO NOT DAILY WITH THIS EXHAUST!!!! I have learnt my lesson, cannot recommend for anything outside of track use....

      DonovanJ

      Year: 2017 Submodel: V6

      Helpful (1)

    • 4/5

      Installation Time: Less than 1 Hour

      July 08, 2018

      Sounds great for an ecoboost

      Only reason I gave 4 instead of 5 stars is because of the price and price to install if you don’t have your own lift.

      ConnerM

      Year: 2018 Submodel: EcoBoost

      Helpful (1)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $100-$250

      July 04, 2018

      Signature eco-boost mustang sound

      I combine this with a Borla 40670. Replacing resonator with the Borla #40670. Beautiful clean sound. No drone at highway speed. The way an Ecoboost Mustang should sound.

      JesusD

      Year: 2017 Submodel: EcoBoost

      Helpful (1)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: 0-$100

      July 01, 2018

      Great Product Price

      You can't beat the price for an axle back exhaust, I combined it with a y pipe sounds pretty good not to loud just right. It's a 4 banger so it will never roar like a V8 regardless of your setup.

      BigLou

      Year: 2015 Submodel: EcoBoost

      Helpful (1)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $100-$250

      June 27, 2018

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

      Great Exhaust

      Perfect tone and loudness for the V6. My set up includes an X-pipe and this exhaust, little drone but overall great buy.

      AnthonyL

      Year: 2017 Submodel: V6

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      June 24, 2018

      Roar

      At High RPM this exhaust really sounds aggressive. Breaks a lot of necks and if your car is running hot enough and the engine is warm enough it does have a little bit of back fire (cracks and pops) that everyone wants. Easy install and really simple look with bigger and fuller exhaust tips.

      EcoBeast

      Year: 2017 Submodel: EcoBoost

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      June 20, 2018

      Great for the money

      Decent deeper tone. Pair with scavenger x pipe and its loud.

      NathanielE

      Year: 2015 Submodel: EcoBoost

      Helpful (2)

    • 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 (3)

    • 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 (3)

    • 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 (3)

    • 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 (4)

    • 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 (4)

    • 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 (4)

    • 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 (2)

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