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Flowmaster American Thunder Cat-Back Exhaust (87-93 LX; 1986 GT)

Item 18467
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Market Price $493.99 You Save 21% ($101.63)
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Ship to: Ashburn - 20149
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    Features & Details

    • Aggressive Flowmaster Sound
    • Super 44 Series Mufflers
    • Mandrel-Bent Tubing
    • Durable Aluminized Steel Construction
    • 2.5" OEM Style Aluminized Steel Tips
    • Fits 1987-1993 LX 5.0 and 1986 GT Mustangs
    Flowmaster Sound. The Flowmaster American Thunder Cat-Back exhaust system with its mandrel bent tubing will improve your 1987-1993 LX or 1986 GT Mustangs exhaust flow for an increase in power. Their included Super 44 Series Mufflers with attached hangers 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 with 25" Long by 2.5" diameter OEM style tips for great muscle car looks and sound.

    Application. This Flowmaster American Thunder Cat-Back exhaust system is designed to fit the 1987-1993 LX 5.0 and the 1986 GT Mustangs equipped with the iconic 5.0L V8 engine.

    Fitment: 1986 1987 1988 1989 1990 1991 1992 1993 Details

    MPN# 17113

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    • (2) Muffler Assemblies
    • (2) Over axle pipes/Exhaust Tips
    Installation Info
    Tech Specs
    Cat-Back Exhaust Specifications
    Piping Material: Aluminized Steel Tip Material : Aluminized Steel
    Piping Size: 2.5" Tip Size: 25"L x 2.5" diameter
    Muffler Type: Chambered Fitment: 87-93 LX and 86 GT Mustangs
    Will it fit my Mustang?

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        Questions & Answers (1)

        1 Top Rated Question

        will this bolt up to my bbk h-pipe

        • You will most likely need to do some modifications in order to have this cat-back bolt up to your h-pipe. You may need to weld it to make sure everything is connected properly.

        Helpful (0)
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          Customer Reviews (3) Write a Review

          Overall Rating 3.7

          out of 5 stars

          Installation Time:Full Day

          • Loudness / Volume 5 5
          • Exhaust Note 4.666667 4.7
          • Fit & Finish 3.666667 3.7
          • Bang For Your Buck 4.666667 4.7

          • 4/5

            Installation Time: Afternoon

            June 05, 2017

            Amazing Sound, Decent price

            I am a mechanic by trade so any sort of bolt-on application is fairly easy and straight forward. My only complaint is the fitment near the rear axles and tires. I made them work but the pipes are closer to the rear tires and axles than I would like them to be. A couple hours after work and I was done. If you can use a cutting wheel and some basic hand tools this project is pretty easy. It helps to have access to a lift too. I would rather pay someone if I had to lay on the ground to install anything under the car. As far as loudness and exhaust note goes I wish Ford would just start putting Flowmaster mufflers on their Mustangs from the factory. These are probably the first performance modification done by every Mustang owner. They sound amazing and really bring out the signature Mustang exhaust sound. Louder than stock but not obnoxiously loud. I have shorty headers, catted x-pipe and the Flowmasters and my exhaust sounds aggressive but not over the top. Bang for the buck is undetermined. Not sure of the performance gains. I figure they are minimal as cams, heads and intake are where most of the power is made in the older pushrod 5.0 engines. Price-wise you can expect to pay about the same price for this system on other Mustang performance web sites.


            Year: 1993 Submodel: LX

            Helpful (8)

          • 3/5

            Installation Time: Full Day

            June 27, 2016

            not bad

            it is definitely not a direct fit as the description says,the connection to my bbk h-pipe was average at best,either have it welded or put plenty of ultra copper joint seale on it,the opening that connects to the h-pipe is not open enough,i wish the desciptions would just be honest and say either some modifications are nesessary or not a direct fit,but when you want to sell products you can not always be honest


            Year: 1988 Submodel: Other

            Helpful (9)

          • 4/5

            Installation Time: Weekend

            January 20, 2015

            They are not direct fitments

            I purchased these exhaust on a Friday and got them on a Tuesday great shipping time but when I came to put them on the muffler mounted fine but the tailpipes would not go over the axle luckily I can weld so I had to buy couplets and cut the tail pipes in half then weld them back together where they fit, if you don't know how to weld take them to a shop but after the install they are a good nice exhaust the sweet spot is 2k rpms


            Year: 1990 Submodel: Other Massillon, OH, USA

            Helpful (9)

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