Flowmaster 817248 - American Thunder Cat Back Exhaust System

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Flowmaster 817248 - American Thunder Cat Back Exhaust System

This part fits

  1. 2004 Ford Mustang SVT Cobra 4.6L V8 cid:281
  2. 2003 Ford Mustang SVT Cobra 4.6L V8 cid:281
  3. 2001 Ford Mustang SVT Cobra 4.6L V8 cid:281
  4. 1999 Ford Mustang SVT Cobra 4.6L V8 cid:281
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About this product

Part #: 817248

For the person who wants the look of a traditional dual exhaust system with all the benefits that a Flowmaster Cat-back exhaust system provides. D.O.R. (Dual out rear) systems are the perfect choice. American Thunder systems deliver a moderate to aggressive interior and exterior tone and are suited to the enthusiast who wants their performance to be heard. 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.

Install photos (1)

For the American Thunder Cat Back Exhaust System

More Details

Exhaust SeriesAmerican Thunder
Exhaust TypeDual
Exit PositionDual Rear
Exit StyleStraight
Heat Shield AttachedNo
Inlet Diameter2.500 in.
Inlet Inside Diameter2.500 in.
MaterialStainless Steel
Muffler Count2
Muffler Part NumberKit Only
Muffler SeriesSuper 40 Series
Outlet Diameter2.500 in.
Outlet Outside Diameter2.500 in.
Single or DualDual
Sound LevelModerate
System TypeCat Back
Tail Pipe Diameter2.500 in.
Tip Diameter3.000 in.
Tip Quantity2
TitleFlowmaster 817248 Cat-back System 409S - Dual Rear Exit - American Thunder - Moderate Sound
Tubing Diameter2.500 in.
Additional Documents
  1. Certificate of Originpdf
  2. Technical Drawingpdf
  3. Installation Instructionspdf
  4. Warrantypdf

See what our community says about flowmaster products

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What made you choose this particular product?
Quality and familiarity with sound.
Is this your first time buying from this brand? Did you consider other brands?
Was it easy to install? Any installation tips that will help others?
A little cumbersome on the garage floor, but very straight forward and fairly simple (exception of left side fixed bolt bracket from existing pro chamber :o ).
Once you've had a chance to use the product, did it meet your expectations?
Any additional comments?
I sought a sound change toward something a little less aggressive. I never knew what exactly the existing cat back brand was. They were (well, I still have them in the garage) quality built, but very aggressive,, maybe 1 chamber in each muffler albeit thin. The sound went from a rabid crackle to a now lower tone rumble. Aggressive cam sound with the stroke and metallic courtesy sound from headers are all still there. ;)
View on Adm's build
California prop 65 warningWARNING: Cancer and Reproductive Harm

*Some manufacturer restrictions apply.

About Flowmaster

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.

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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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