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For the person who is looking for a complete Header-back dual exhaust system with a performance sound. This system is mandrel bent for maximum performance and includes specially selected mufflers. American Thunder 2.5 in. systems generally deliver a moderate to aggressive interior and exterior tone and are suited to the enthusiast who wants their performance to be heard. The sound level will depend greatly on the engine and level of modification. Like all Flowmaster systems, the benefits include improved throttle response, power and mileage. Designed for an easy fit, these systems include all necessary parts and hardware for easy installation.
|Automotive Item Grade||High Performance|
|Exhaust Pipe Wall Max Gauge||16|
|Exhaust Series||American Thunder|
|Exit Position||Dual Rear|
|Heat Shield Attached||No|
|Inlet Diameter||2.500 in.|
|Inlet Inside Diameter||2.500 in.|
|Mount Type||Uses New Hangers (Included)|
|Muffler Series||Super 40 Series|
|Outlet Diameter||2.500 in.|
|Outlet Outside Diameter||2.500 in.|
|Single or Dual||Dual|
|System Type||Header Back|
|Tail Pipe Diameter||2.500 in.|
|Tip Diameter||2.500 in.|
|Tip Type||Straight Cut|
|Title||Flowmaster 817390 Header-back System 409S - Dual Rear Exit - American Thunder -Moderate/Aggressive|
|Tubing Diameter||2.500 in.|
*Some manufacturer restrictions apply.
Manufacturer of performance exhaust systems, mufflers, cold air intakes, turbo boost modules, catalytic converters, race mufflers, headers and numerous exhaust accessories for late model cars, trucks, off-road, Jeeps, SUV’s, classic muscle cars, powersports vehicles and more. Flowmaster® gives you lots of exhaust choices with 12 designs of chambered mufflers, 3 styles of our exclusive “laminar-flow” mufflers and a new line of FlowFX “straight-through” performance mufflers, along with 5 sound categories of exhaust systems, giving you the customer, the power to custom tailor the sound of your vehicle whether you prefer mild, moderate or aggressive tones and sound levels.
Based in California with 3 warehouses across the country, we’re sending out shipments everyday of the week, even Saturdays. Because your next mod shouldn’t have to wait.
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