Flowmaster Stainless Steel "American Thunder" Axle Back Exhaust for 2011-2012 Mustang GTs and Shelby GT500s.The Ford 5.0-liter engine is back and delivers an incredible 412 Camaro-smokin' horsepower. To match the factory's re-issue of the famous 5.0-liter nameplate, Flowmaster set about re-engineering their American Thunder system to deliver that classic 5.0-liter sound, along with additional fuel mileage and power.
This new Flowmaster American Thunder axle-back kit for the 2011 Ford Mustang features a pair of stainless steel, specially built Classic Two Chamber mufflers that provide a very deep and aggressive sound level, and is suited to the enthusiast who wants a distinctive and powerful exhaust note.
The system is constructed with mandrel bent 3" diameter 409S stainless steel tubing for maximum durability and includes a 4" diameter polished tips with embossed logo that exit through the factory rear valence cutouts. A true bolt-on that includes everything you need to easily install at home in your driveway with basic hand tools. As with all Flowmaster products, they are built in the USA.
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This product will fit the following Ford Mustang years:
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Alex: Thank you for having me Bill. How are you doing today?
Bill: I'm doing good. We all know the two chamber Flowmaster. If you had a Fox Body back in the day you had some Flowmasters on it. But what else can you tell us about your company?
Alex: Well, Flowmaster is an aftermarket performance exhaust manufacturer, Bill, that started off on the racetracks. Ray Flugger, the founder of the company, designed mufflers for racers that were being hammered for excessive noise limits. Flowmaster presents that opportunity where you're able to reduce those dB levels without having to hurt or kill performance. Flowmaster is also one of the most significant speed parts of all time where we are actually an innovative product different from the standard that's out there.
Bill: The two chamber Flowmaster that was the original product he was selling out of a suitcase.
Alex: The 40 Series, except with some slight modifications on the case itself. Back then it was a square case and now it's more of a round oval.
Bill: The other mufflers you have here, what can you tell me about them?
Alex: Here we have a 50 Series Delta Flow to the far right, which is a three chamber design, a little more subdued, a little mellower for those that are looking for less interior resonance. In the middle here we've got a Super 40, which is a two chamber design, a little thicker, a little wider, which is set up to handle higher output applications. To the far left we've got a Super 44, which is the latest and greatest two chamber design that Flowmaster has released in recent years.
Bill: Is that still based off of the original design?
Alex: That is correct.
Bill: I know Flowmaster has a lot of kits available for the 2005 and newer Mustangs. What can you tell me about these two kits you brought with you today?
Alex: Well, Bill here we've got a Force II exhaust system from Flowmaster. It's a direct bolt on axle back 409 stainless steel with a limited lifetime warranty, fully constructed here in the U.S. It's got the rolled edge stainless steel tip with the nice four inch diameter. All of the hardware, everything you need, is included within the kit so you don't have to buy any additional accessories.
This would probably take you an hour and a half to install out of your own garage on a weekend. Very subdued, very mellow kind of tone, something designed for someone who's looking for more of a performance aspect with a little bit of rumble, nothing too wild, nothing too crazy.
Over here on the right we've got the Outlaw System. The Outlaw is very noticeable, very aggressive. It's the 'hear me from a mile away' type of sound, something I would only recommend to those who are fully aware of what they're getting. It utilizes an Outlaw race muffler, basically a muffler that was designed for race applications that are required to run mufflers without a specific dB limit. Again, I only recommend it to those that are looking for the aggressive tone from Flowmaster. It is fully built out of stainless steel, lifetime warranty as well.
Bill: The Outlaw is available for '05 and up for both the 5.0 liter and the 4.6 liter cars?
Alex: That is correct.
Bill: We know Flowmaster that has systems that fit all year Mustangs, but I heard you guys are getting in other parts of the exhaust as well?
Alex: That's right, Bill. We actually just released a full line of stainless steel headers, ceramic coated, very high end piece. They look great. It'll compliment the rest of your exhaust components. We also just released a full line of catalytic converters, both 49 state and carb certified.
Bill: If you're looking for that classic Flowmaster sound, it doesn't matter what year your car is, Flowmaster has a system that will fit your Mustang.