Flowmaster® 817412 - American Thunder™ Stainless Steel Dual Header-Back Exhaust System (Dual Side Exit)

Flowmaster Performance Exhaust Systems
Flowmaster® - American Thunder™ Stainless Steel Header-Back Exhaust System (Dual Side Exit)Flowmaster® - American Thunder™ Stainless Steel Header-Back Exhaust System (Dual Side Exit)Flowmaster® - American Thunder™ Stainless Steel Header-Back Exhaust System Installation InstructionsFlowmaster® - Exhaust TypesFlowmaster® - American Thunder™ Exhaust Systems Aggressive SoundFlowmaster® - American Thunder™ Exhaust System on Buick Le SabreFlowmaster Authorized Dealer
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American Thunder™ Stainless Steel Dual Header-Back Exhaust System (817412) by Flowmaster®, AGGRESSIVE SOUND. Super 40 Series Mufflers. Dual Side Exit. 2.5" Tubing. Includes H-Pipe. American Thunder gives you the classic AGGRESSIVE, MODERATE or MILD sound (depends on application and exhaust type) of a Flowmaster chambered exhaust, which is the classic sound of classic American big performance engines. This is a system that gives the most sedate vehicle a performance rumble. American Thunder is perfect for a wide range of cars, from ponies to sleepers.

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  • Moderate Sound
  • Increases Power
  • Increases Torque
  • Every System Tuned on Dynamometer
  • Perfect Fitment

American Thunder gives you exactly the sound that is promised by the name of the series. The exhaust sound of the American Thunder system has become a symbol of American power that is recognized all over the world. American Thunder is the most popular of the Flowmaster exhaust systems, enhancing power, torque, throttle response and mileage for automobile enthusiasts all over the world.

All Flowmaster exhaust systems give the same improvement of performance. All Flowmaster exhaust systems produce a beautiful deep performance tone. Choosing between the five different exhaust systems is not a technical decision – it is all up to your personal taste. It’s A Sound Decision™. The racing origin is evident in every Flowmaster exhaust system. All the five series of systems are tuned for maximum performance. They differ in technology and tuning, and thus in tone and character, giving you a performance engine sound to your personal liking.

Flowmaster exhaust systems employ two unique technologies, the patented Delta Flow and the Laminar Flow. They give different characters of sound and can be tuned to achieve the desired exhaust note. Flowmaster Exhaust System Technology is so versatile and gives such a high degree of control that it is used both by racers, who want maximum power, and by the U.S. Air Force in Stealth applications, where maximum silence and minimum heat emissions are prime considerations.

Be it for a domestic or import truck, SUV, off-road warrior, daily driver, muscle car, euro-spec cruiser or sport compact vehicle, Flowmaster technicians personally hand select the right muffler, tubing size, resonator, and tip to make the process easy for you. Best of all, Flowmaster stainless steel exhaust systems are covered by a Limited Lifetime Warranty; ensuring that your exhaust will last as long as you own your vehicle. If you choose aluminized steel products, Flowmaster backs them up with a 3-year warranty.

Brand: Flowmaster       Part Number: 817412       UPC: 700042024025
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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.

Vehicle FitmentThis part is compatible with 27 vehicle(s)
Year Make Model Fitment Notes
1967 Buick Gran Sport
1967 Buick Le Sabre    Base 5.6L
1967 Buick Skylark    4.9L / 5.6L / 6.6L
1967 Chevy Chevelle    SS 6.5L; Base 3.8L / 4.6L / 6.5L
1967 Pontiac GTO
1967 Pontiac Grand Prix
1967 Pontiac LeMans
1966 Buick Gran Sport    6.6L
1966 Buick Le Sabre    Base
1966 Buick Skylark    4.9L / 5.6L / 6.6L
1966 Chevy Chevelle    SS 6.5L; Base 3.2L / 4.6L
1966 Pontiac GTO
1966 Pontiac Grand Prix    6.4L
1966 Pontiac LeMans    6.4L
1965 Buick Gran Sport    6.6L
1965 Buick Le Sabre    Base
1965 Buick Skylark    4.9L / 6.6L
1965 Chevy Chevelle    SS 4.6L / 6.5L; Base 3.2L / 4.6L
1965 Pontiac GTO    5.3L / 6.4L
1965 Pontiac Grand Prix    6.4L
1965 Pontiac LeMans    6.4L
1964 Buick Le Sabre
1964 Buick Skylark    4.9L
1964 Chevy Chevelle    Base 4.6L
1964 Pontiac GTO    5.3L / 6.4L
1964 Pontiac Grand Prix    6.4L
1964 Pontiac LeMans    6.4L
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