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Flowmaster American Thunder Cat-Back Exhaust; Stainless Steel (99-04 GT, Mach 1)

Item 18436
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      Video Review & Installation

      Hi I’m Justin with AmericanMuscle.com and I’m taking a closer look at Flowmaster’s stainless steel American Thunder Cat-Back exhaust, fitting the 99-04 Mustang GT and Mach 1. The two biggest features with this system are of course the full 409 grade stainless steel constructions throughout, and also the super 40 series mufflers, which give you that classic Flowmaster throaty rumble. The stainless steel tubing features a 2.5” diameter and mandrel bends throughout, all of which exists through these 3” hand polished OE style tips. Due to the design of your factory exhaust you will need to cut it off in sections using a saw or something similar. Once you get that out of the way, getting the American thunder bolted up, is a pretty straightforward that should take you roughly 2 hours using some standard hand tools and the included clamps. Now let’s hear how the stainless American Thunder sounds compared to our factory exhaust.

      Product Information

      Features, Description, Reviews, Q&A, Specs & Installation

      Features

      • Aggressive Flowmaster Sound
      • Super 40 Series Mufflers
      • 3" Polished Stainless Steel Tips
      • Mandrel-Bent Tubing
      • 409 Stainless Steel Construction
      • Fits 1999-2004 GT, Mach 1, and Bullitt Mustangs

      Description

      Flowmaster Sound.The Flowmaster American Thunder Cat-Back exhaust system with its mandrel bent tubing will greatly improve your 1999 to 2004 Mustangs exhaust flow for an increase in power, and their included Super 40 Series Mufflers will improve your exhausts sound for a deeper throatier muscle car exhaust note.

      Stainless Steel Construction. Constructed from mandrel bent 2.5" 16 gauge 409 stainless steel tubing for it's corrosion resistant properties, the Flowmaster American Thunder Cat-Back features their Super 40 Series chambered mufflers with 3.0" diameter OEM style polished stainless steel tips for great muscle car looks and sound.

      Application. This Flowmaster American Thunder Stainless Steel Cat-Back exhaust system is specifically designed to fit the 1999-2004 GT, 2001 Bullitt, and 2003-2004 Mach 1 Mustangs for both impressive looks and sound. This system will not fit the SVT Cobra Mustangs.

      Fitment: 1999 2000 2001 2002 2003 2004 Details

      Flowmaster 817312

      CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Right muffler assembly
      • (1) Left muffler assembly
      • (1) Right tailpipe assembly
      • (1) Left tailpipe assembly
      • (2) Clamps
      • (4) Lock Washers

      Tech Specs

      Cat-Back Exhaust Specifications
      Piping Material: 409 Stainless Steel Tip Material : Polished Stainless Steel
      Piping Size: 2.5" Tip Size: 3.0"
      Muffler Type: Chambered Fitment: 1999-2004 GT, Bullitt and Mach 1 Mustangs
      4.7

      Customer Reviews (100+)

        Reviews of Flowmaster Exhaust products have an average rating of 4.7 out of 5

          Questions & Answers

          10 More Questions

          Will It Fit My Mustang

          • Bullitt - 01
          • GT - 99, 00, 01, 02, 03, 04
          • Mach 1 - 03, 04

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