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Flowmaster American Thunder Cat-Back Exhaust (87-93 GT)

Market Price $497.99 You Save 13% ($65.02)
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  • Item 18405
  • MPN# 17116

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    Features & Details

    • Aggressive Flowmaster Sound
    • Super 44 Series Mufflers
    • Mandrel-Bent Tubing
    • Durable Aluminized Steel Construction
    • Fits 1987-1993 GT Mustangs
    Flowmaster Sound . The Flowmaster American Thunder Cat-Back exhaust system with its mandrel bent tubing will improve your 1987-1993 GT Mustangs exhaust flow for an increase in power, and their included Super 44 Series Mufflers will improve your exhausts sound for a deeper throatier muscle car exhaust note.

    Quality Construction. Constructed from mandrel bent 2.5" 16 gauge aluminized steel tubing for it's corrosion resistant properties the Flowmaster American Thunder catback features Super 44 Series chambered mufflers for that classic muscle car sound.

    Fitment. This Flowmaster American Thunder Cat-Back exhaust system is designed specifically for the 1987 to 1993 GT Mustangs for both great a fit and great sound.

    Fitment: 1987 1988 1989 1990 1991 1992 1993 Details

    What's in the Box
    Hardware included:
    • (2) Clamps, Attached Hangers
    Installation Info
    Tech Specs
    Cat-Back Exhaust Specifications
    Piping Material: Aluminized Steel Tip Material : Aluminized Steel
    Piping Size: 2.5" Tip Size: N/A
    Muffler Type: Chambered Fitment: 87-93 GT Mustangs
    Will it fit my Mustang?
    • GT - 87, 88, 89, 90, 91, 92, 93

    Fits GT Only

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    3 Questions / 3 Answers

    Ask a Question

    Will this Catback mount to a stock h-pipe?


    • Yes it will! I just installed the cat back kit to a completely stock 91 GT.


    Helpful (1)

    Hi will this exhaust fit my 88 gt 5,0 convertible


    • The Flowmaster American Thunder Cat-Back Exhaust (87-93 GT) will fit your 1988 GT convertible. This exhaust will fit any GT from 87-93.


    Helpful (0)

    Will the American Thunder Catback exhaust system fit with BBK's long tube headers?


    • The Flowmaster American Thunder Cat-Back Exhaust are design to mount in the factory mid-pipe location. The BBK long tubes and mid-pipe meet in the stock location, so this cat-back will work well.


    Helpful (0)

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    Customer Reviews (27) Write a Review

    Overall Rating 4.9

    out of 5 stars

    Installation Time:Afternoon

    Installation Cost:$100-$250

    • Loudness / Volume 4.631579 4.6
    • Exhaust Note 4.947369 4.9
    • Fit & Finish 4.736842 4.7
    • Bang For Your Buck 4.789474 4.8

    • 5/5

      August 10, 2009

      Great Exhaust

      The exhaust is great and is an easy install. Everything that I needed was in the box and ready to install. Great price and free shipping made it even more worth it. Keep up the great service americanmuscle i have a 1988 fox body gt with t tops and this has been my website of choice for just about everything i have purchased for my car.


      Year: 1998 Submodel: GT

      Helpful (12)

    • 5/5

      March 31, 2011

      American Thunder exhaust

      Very happy With the system, flowmasters never disappoint. The install was pretty easy and the mendral bent tubing is of exceptional quality. Would absolutely purchase again. On a side note before installing check to make sure all your exhaust hangers are still there and purchase new rubber hangers for the tips out back. Your stock one will likely crumble apart.


      Year: 1990 Submodel: GT

      Helpful (9)

    • 5/5

      February 22, 2010

      AW,,,, SOME SOUND !

      It took me about 6 hour's to install this system. Dad gum knuckle buster!!!! But Hay call me slow with A socket set and Saw-Saw. My Stang sure ant slow. It sure talk's to me now. Great Rumble & Sound.


      Helpful (9)

    • 5/5

      September 15, 2009


      This exhaust is very nice. Sounds great with my off road H-pipe. I ordered this on the 9th and got it the 10th with the standard shipping. Fast!


      Helpful (9)

    • 5/5

      Installation Time: Full Day

      June 23, 2013

      Exactly what I wanted.

      Combined with the BBK off road x pipe this system gave my mustang the exact sound I was looking for. We did the entire header back exhaust and smog pump delete in about 6 hours. Love the set up!


      Year: 1990 Submodel: GT MA

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      January 24, 2017

      True American Thunder

      Combined with BBK midpipe headers and this makes the most wicked sound. It has a deep/bass howl and has crackling backfire. Install is very easy for the American Thunder and it lives up to its name!


      Year: 1993 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      November 09, 2016

      Great sounding exhaust

      received the exhaust within two days, awesome! Took a couple of hours to install and sounds great. Very happy with this purchase


      Year: 1989 Submodel: GT

      Helpful (2)

    • 4/5

      August 03, 2016

      Easy install

      Exhaust went on very easy. Also gave a nice Rumble to the car sounds like it should the only negative thing is the hardware is very weak that comes with the kit. Other than that I would have given it 5 stars


      Year: 1989 Submodel: GT

      Helpful (2)

    • 5/5

      July 21, 2016

      Flowmaster Cat Back

      Love my Flowmaster Cat Back exhaust. Fit perfectly and sounds great. Installation was a breeze. Came with eveything I needed. Thanks American Muscle.


      Year: 1988 Submodel: Other

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      December 23, 2015

      A unbelievable deal!!!

      I love this exhaust sounds excellent. Was quick to install looks good coming out the tail of my car. Just a overall good buy, reasonable price, and shipped very fast. I love it!!!


      Year: 1991 Submodel: GT Newark, Nj

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      January 07, 2015

      American Thunder for the perfect sound

      This kit came with everything I needed for a smooth install and a perfect fit. The sound is dead on what i wanted when I ordered this product (which got to my house very quickly AND FREE!). The sound is the perfect Mustang sound that I dreamt of.


      Year: 1991 Submodel: GT Athens, GA, USA

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      May 05, 2014

      Great fit, fast shipping

      Great exhaust, was on sale. Fit with no issues. Great sound, as always with flowmasters. Shipping was fast to Canada Thanks AM!.


      Year: 1990 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      August 15, 2013

      excellant sound

      My mustang has that distinct mustang sound now. Mean and powerful.


      Year: 1987 Submodel: GT Barrington, IL, USA

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      July 27, 2012


      This is an amazing exhaust that went right in. When it showed up in smaller boxes I thought it would be hard work but it bolted right in. I used the Pypes Catted X-Pipe (79-95 5.0L) and Ford Racing Double Hump Adjustable Transmission Crossmember with it. I went home from work with an exhaust leak and plugged cats, tinkered in the garage for an afternoon, and went back the next day turning heads and getting compliments. This is an awesome upgrade at a fantastic price. I won't go anywhere else for parts.


      Year: 1985 Submodel: GT Ogden, UT, USA

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      June 23, 2012

      Intimidating GT

      I have noticed that my convertible GT sounds nice and it even feels like its is breathing easier. I paired mine up with dynomax headers and it sounds nice. What more can you ask for its a flowmaster exhaust and it was 300 dollars well spent.


      Year: 1989 Submodel: GT Sunnyside, WA, USA

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      August 28, 2017

      It's flowmaster...nuff said

      Putting this exhaust in took me about 2.5 hours on my back in my garage. That includes cutting out the old. It's the signature flowmaster sound we all know and love.


      Year: 1990 Submodel: GT

      Helpful (1)

    • 4/5

      Installation Time: Afternoon

      December 17, 2016


      Great purchase and sounds great but the clap isnt really doing very well ended up welding everything so good luck with your installation


      Year: 1992 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      June 30, 2014

      Easy install.

      My Flowmaster cat back system arrived quickly as my orders usually do from American Muscle. I installed the system in my 1989 Mustang GT in my driveway. The fit was great as usual.


      Year: 1989 Submodel: GT Delran, New Jersey

      Helpful (1)

    • 5/5

      Installation Time: Shop Install

      July 04, 2013

      Love this Flowmaster catback exhaust!

      My mechanic said the installation went without a single hitch. This system really releases the wild side of my 'stang. I absolutely love the deep, resonant "Flowmaster" tone this system produces. At speed, there is no droning. I have only had this system installed a couple of days now, and have received numerous compliments on how nice the car sounds. Thanks to Flowmaster, and American Muscle, for an outstanding product.


      Year: 1987 Submodel: GT Kendallville, IN, USA

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      January 20, 2012

      Beautiful explosion of sound

      These exhaust are jus amazing. If you want loud uncontrolled sound...these exhaust are what you are looking for. Amazing when you step on the peddle especially in the High rpm. Just a amazing explosion of raw sound. Awesome flowmaster exhaust.


      Year: 1989 Submodel: GT Orlando fl

      Helpful (1)

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