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Flowmaster American Thunder SS Header-Back Exhaust for 64 - 66 Mustang - 817273

Flowmaster American Thunder SS Header-Back Exhaust for 64 - 66 Mustang - 817273

Note 1: Does Not Fit GT or Convertible

Flowmaster American Thunder true dual exhaust systems are engineered with maximum performance in mind. These systems feature specially tuned mufflers, cross-over pipes, clamps, hangers and mounting hardware. If you're looking for the famous Flowmaster tone look no further. American Thunder will deliver the aggressive tone you want as well as the performance you demand.
Header-back System
Mandrel bent 16 gauge stainless steel tubing
Includes hangers and hardware for easy installation
Moderate Sound exterior exhaust tone


Fits 1964 to 1966 Mustang. Does not fit GT or convertibles.

Flowmaster has its roots in solving the engine noise problems encountered by California racers in the 1980s. In 1983 Flowmaster’s founder, Ray Flugger, created his first patented design of racing silencers, which dampened noise with minimal loss of power. Ray attached handles to ease carrying the square shaped race mufflers through the race pits, and the mufflers became known as the "suitcase mufflers." Today, the innovative Flowmaster mufflers are the result of years of development with top race engine builders, thousands of hours of dyno research and "real-world" on-track testing.

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