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Flowmaster High-Performance Catted Y-Pipe (99-04 V6)

Item 18464
AmericanMuscle no longer carries the Flowmaster High-Performance Catted Y-Pipe (99-04 V6). Please check out 2015-2023 Mustang Mid-Pipes Exhaust for an updated selection.
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    Product Information

    Features, Description, Reviews, Q&A, Specs & Installation


    • Improves Exhaust Flow and Sound
    • Classic Muscle Car Rumble
    • 2-1/4" Mandrel-Bent Stainless Steel Tubing
    • High Flow Catalytic Converters Included
    • 49 State Emissions Legal
    • For Use with Stock Manifolds or Shorty Aftermarket Headers
    • Fits 1999-2004 V6 Mustangs


    Regain Lost Power. Replace those clogged or blown-out stock catalytic converters with high performance Flowmaster replacements to regain lost horsepower and torque.

    Muscle Car Rumble. This free flowing Flowmaster Mid Pipe will not only improve performance, but it will also add a deep muscle car rumble to the sound of your exhaust with its classic "Y" crossover pipe design.

    Quality Construction. Constructed in the USA from durable 2.25" 16 gauge 409 stainless steel tubing for it's corrosion resistant properties this Flowmaster Y-Pipe features four high flow catalytic converters, two main cats and two pre-cats. The included catalytic converters feature a durable ceramic substrate material making them perfect for naturally aspirated applications.

    49 State Legal. The included catalytic converters meet or exceed USEPA standards and are 49 state emissions legal. They are not legal for use in the state of California.

    Application. This Flowmaster High Performance Catted Y-Pipe is designed to be a direct bolt-on replacement for the 1999-2004 3.8L or 3.9L V6 Mustangs with either aftermarket shorty headers or the stock manifolds installed.

    CA Residents: WARNING: Cancer and Reproductive Harm -

    Installation & What's in the Box

    Installation Info

    What's in the Box

    • (1) Catted Y-pipe
    • (2) clamps

    Tech Specs

    Mid Pipe Specifications
    Style Mid Pipe: "Y" Type Headers Required: Shorty or stock manifolds
    Piping Material: Stainless Steel Piping Size: 2.25"
    Catalytic Converter: "Yes" Fitment: 1999-2004 V6 Mustangs

    Customer Reviews (80)

      Questions & Answers

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