For the person who is looking for a complete cat-back dual exhaust system with an aggressive tone.Learn More

Flowmaster's race-oriented American Thunder Cat-back system is designed to mount behind the factory catalytic converters, or most OEM style aftermarket H-pipes. These systems are mandrel bent for maximum performance and include Super 44 series mufflers. This American Thunder system delivers a super aggressive interior and exterior tone and is suited to the enthusiast who wants the most aggressive components they can purchase. Like all Flowmaster systems, the benefits include improved throttle response and power. Designed for an easy fit, these systems include all necessary parts and hardware for easy installation.Learn More

Flowmaster 1998 GT American Thunder Catback System

• 2.5" Outlet
• 40 Series Delta Flow Mufflers
• Stainless OEM Style Tips
• American Thunder

American Thunder
Looking for the famous, full-on "Flowmaster tone?" Look no further. This American Thunder system will deliver the aggressive tone you want, as well as the performance you demand.

Delta Flow Technology
Developed from Flowmaster's line of Delta Force® race mufflers, Delta Flow® technology provides superior scavenging of exhaust gases even over a comparable (standard) Flowmaster muffler. This results in increased horsepower, torque and fuel economy, along with reductions in exterior sound levels and interior resonance. These three deflectors function properly only when they've been precisely placed and welded to exact specifications. Together they provide superior reductions in exterior sound levels as well as resonance transmitted through the exhaust system and into the vehicle.

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