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Flowmaster American Thunder Catback Exhaust (12 BOSS)

1 Reviews
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  • Item #18429
  • MPN# 817553

  • Market Price $1,025.99
  • You Save 10% ($102.54)
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  • Aggressive Flowmaster 60-Series Delta Flow Sound
  • Durable 409 Stainless Steel Construction
  • 3" Mandrel Bent Tubing
  • 4" Polished Stainless Steel Tips
  • Includes Two Flowmaster 60 Series Mufflers
  • Fits 2012 BOSS
Signature Flowmaster Sound. Give your BOSS Mustang that unmistakeable Flowmaster sound with the American Thunder Catback Exhaust system from AmericanMuscle. The Flowmaster American Thunder Catback Exhaust with its mandrel bent tubing will greatly improve your Mustangs exhaust flow for an increase in power, and the included 60 Series Delta Flow Mufflers will improve your exhausts sound for a deep aggressive muscle car exhaust note.

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.

Quality Construction. Constructed from durable 3" 16 gauge 409 stainless steel tubing for it's corrosion resistant properties the Flowmaster American Thunder Catback features two 60 Series Delta Flow American Thunder 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 American Thunder Catback exhaust system is designed to fit the 2012 5.0L Coyote Powered BOSS Mustang equipped with either aftermarket shorty headers or the factory manifolds. Does not fit GT or Shelby GT500 models.

Fitment: 2012 Details

What's in the Box
  • (1) H-pipe
  • (2) Over-axle pipes
  • (2) Muffler assemblies
  • (4) Clamps
  • Installation hardware
Installation Info
Tech Specs
Axleback Exhaust Specifications
Piping Material: 409 Stainless Steel Tip Material : Polished Stainless Steel
Piping Size: 3.0" Tip Size: 4.0"
Muffler Type: Chambered Fitment: 2012 BOSS
Will it fit my Mustang?
  • Boss 302 - 12

Fits 2012 BOSS Mustang Only. Designed to be used with the factory manifolds or aftermarket shorty headers installed.

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2 Questions / 1 Answers

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Performance Difference? What kind of performance increase will I see if I install this exhaust system onto my 2012 Boss? What is the difference between this exhaust and the stock exhaust?

jbebout1 Year: 2012 Model: Boss

  • You may see an additional 5+ HP with this exhaust over stock. I believe the stock exhaust has 3" tubing while the factory is 2.75". This will also eliminate the side cutout exhaust if it is on your Boss.

    Catch22COP Year: 2012 Model: GT Top 10 Contributor

    Good Answer (0) (8)

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Fit Laguna Seca? Will this fit a '13 Boss 302 Laguna Seca? Flowmaster's website isn't much help.

oponox Year: 2013 Model: Boss

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Customer Reviews (1) Write a Review

Overall Rating 4.0

out of 5 stars

Installation Time:Less than 1 Hour

  • Loudness / Volume 4 4
  • Exhaust Note 5 5
  • Fit & Finish 5 5
  • Bang For Your Buck 4 4

  • 4/5

    Installation Time: Less than 1 Hour

    January 18, 2013

    Interior noise level

    The only thing I don't like about this exhaust it the internal noise level while driving. It is LOUD. The external is great.


    Year: 2012 Model: Boss Driving Style: Daily Driver 'Stangs I have owned: 5+

    Helpful (0) (0)

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