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

Market Price $640.99 You Save 12% ($75.04)
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  • Item 18447

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Ship to: Ashburn - 20149
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    Features & Details

    • Aggressive Flowmaster Sound
    • Super 44 Series Mufflers
    • Mandrel-Bent Tubing
    • 409 Stainless Steel Construction
    • Fits 1987-1993 GT Mustangs
    Flowmaster Sound. Give your Mustang that unmistakeable Flowmaster sound with a nice power boost by installing a American Thunder catback Exhaust system. Featuring mandrel bent tubing this Flowmaster system will improve exhaust flow for an increase in power, and the included Super 44 Series Mufflers will improve your exhausts sound for a deeper throatier muscle car exhaust note.

    Stainless Steel Construction. Constructed from mandrel bent 2.5" 409 stainless 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.

    Application. This Flowmaster American Thunder stainless steel Cat-Back exhaust system is designed specifically for use on the 1987 to 1993 GT Mustangs for great looks and great sound.

    Fitment: 1987 1988 1989 1990 1991 1992 1993 Details

    MPN# 817116

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    • (2) Muffler assemblies
    • (2) Over axle pipes
    • (2) Exhaust Tips
    • (2) Clamps
    Installation Info
    Tech Specs
    Cat-Back Exhaust Specifications
    Piping Material: 409 Stainless Steel Tip Material: 409 Stainless Steel
    Piping Size: 2.5" Tip Size: N/A
    Muffler Type: Chambered Fitment: 87-93 GT Mustangs
    Will it fit my Mustang?

      Customer Photos

        Questions & Answers (2)

        2 Top Rated Questions

        Can I get stainles steel super 50 cat back

        • While not in stainless steel we do have this here in terms of a super 50 cat back:

        Helpful (0)

        Hi was wondering if the setup was in all about 7 feet long? Thanks

        • Hi,We do not have a exact length on this Flowmaster American Thunder Cat-Back, But I can tell you that the average Foxbody cat back is around 4.5- 5.5 feet long

        Helpful (0)
        Post Your Question

          Customer Reviews (5) Write a Review

          Overall Rating 4.4

          out of 5 stars

          Installation Time:Afternoon

          Installation Cost:$100-$250

          • Loudness / Volume 4 4
          • Exhaust Note 4.2 4.2
          • Fit & Finish 4.6 4.6
          • Bang For Your Buck 4 4

          • 3/5

            Installation Time: Shop Install

            Installation Cost: $100-$250

            March 27, 2019


            Value seems fair but the exhaust note is less then I expected.


            Year: 1990 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Full Day

            June 19, 2016

            Flowmaster American Thunder Catback - Stainless Steel (87-93 GT)

            Great system. I installed mine with BBK shorty unequal length ceramic coated headers and BBK offroad X pipe from American Muscle. The combo is unbelievable. Not back firing, great sound and super tough. Thanks A.M.


            Year: 1993 Submodel: GT

            Helpful (9)

          • 5/5

            Installation Time: Afternoon

            August 13, 2015

            Flowmaster the master

            Hands down there is no sound on a FOX like a flowmaster. This went on my 93 and I couldnt be happier. Great quality and great sound. What more can you ask for.


            Year: 2006 Submodel: GT West Chester, PA

            Helpful (12)

          • 4/5

            Installation Time: Less than 1 Hour

            July 01, 2013

            Nice exhaust

            My original exhaust broke due to driving my car on a poorly maintained road. My car is all stock so I wanted to keep my new exhaust on the more subtle end with a slight upgrade. This was definitely the right answer. Slightly aggressive without being obnoxious. It fits my cars personality well.


            Year: 1989 Submodel: GT Detroit, MI

            Helpful (9)

          • 5/5

            Installation Time: Less than 1 Hour

            April 19, 2013

            Great sound completes my exhaust upgrade

            Love the sound of the thunder catback. Easy to install and can feel the power. I get plenty of looks as well. My pony sounds like a stud


            Year: 1989 Submodel: GT Oklahoma

            Helpful (11)

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