Free Shipping On Orders Over $49. Details

Talk to a Mustang Enthusiast
M-F 8:30A-11P, Sat-Sun 8:30A-9P
Win $5,000 For Your Mustang! Enter Daily

Magnaflow 3 in. Competition Cat-Back Exhaust (99-04 GT, Mach 1)

Market Price $870.81 You Save 12% ($100.18)
Our Price


FREE Shipping

  • Item 388827

Will this fit your Vehicle?

Change Vehicle Help?
In Stock Ships same business day.
Ship to: Ashburn - 20149
Sorry, please enter a valid US or CA postal code
We're sorry, zip can't be updated at this time.
    Create a list
    Add to New List

    Saved - View your saved items

    We're sorry. We couldn't save this product at this time.

    Features & Details

    • Aggressive Muscle Car Sound
    • Competition Series Bullet Style Mufflers
    • Stainless Steel Construction
    • 3.0" Diameter Mandrel-Bent Tubing
    • 3.0" Diameter Polished Stainless Tips
    • Indented For Use With A 3" Diameter Mid-pipe
    • Fits 1999-2004 GT, Bullitt and Mach 1 Mustangs
    More Power. Stop obstructing your V8 Mustangs performance with the restrictive factory exhaust system and enjoy more power by installing a Magnaflow 3" Competition Cat-Back Exhaust. A Magnaflow 3" Competition Cat-Back will eliminate power robbing restrictions for a measured increase in horsepower and torque at the rear wheels of your GT, Bullitt or Mach 1 Mustang.

    Aggressive Muscle Car Sound. Give your V8 powered 1999-2004 Mustang the aggressive rumble it deserves with a Magnaflow Competition Cat-Back. This premium quality exhaust features free-flowing, straight-through bullet style mufflers that increase power and give your Pony an unmistakable muscle car sound.

    Magnaflow Quality. Constructed from durable 3" diameter mandrel bent stainless steel tubing for it's corrosion resistant properties, this Magnaflow Cat-Back features two straight-through Competition mufflers with brightly polished 3" stainless tips, that exit in the stock locations for impressive muscle car looks and sound. 

    Application. This Magnaflow 3in Competition Cat-Back Exhaust System is specifically designed to fit 1999-2004 GT, 2001 Bullitt and 2003-2004 Mach 1 Mustang models with a Magnaflow or aftermarket 3" Mid Pipe installed.

    Note: Coupon codes cannot be applied to this product.

    Fitment: 1999 2000 2001 2002 2003 2004 Details

    MPN# 16394

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    • (2) Flow Tubes
    • (2) Tail Pipes
    • (2) Competition Mufflers
    • (2) Polished Tips
    • (2) Set Screws w/ Allen Wrench
    • (2) Tip Hangers
    • (6) 1.25" x 2.5" Band Clamps
    • (2) Header Mounting Flanges
    Installation Info
    Tech Specs
    Cat-Back Exhaust Specifications
    Piping Material: Stainless Steel Tip Material : Polished Stainless Steel
    Piping Size: 3.0" Tip Size: 3.0"
    Muffler Type: Straight-through Fitment: 1999-2004 GT, Mach 1, Bullitt
    Will it fit my Mustang?

      Customer Photos

        Questions & Answers (5)

        5 Top Rated Questions

        Hello If I mount Magnaflow 3in cat-back on my Mustang GT 2002 what is best in X or H pipe to complet the exhaust ?

        • The Magnaflow Competition Cat-Back Exhaust - 3in. for the 99-04 GT, Mach 1, Bullitt will sound great with either the H or X mid pipe of your personal choice. The H will deep and throaty toned and the X pipe will be High pitched and Raspy toned. This Magnaflow Cat-Back will be a 3in which will require a 3in Mid pipe to properly bolt up together.

        Helpful (1)

        I have BBK Longtubes with the BBK catless x-pipe, I’m assuming because it’s a 3 in exhaust it’s not adapted down to be compatible with my current x-pipe or am I wrong?

        • That is correct yes. You will either need a step-down adapter or a 3" mid-pipe.

        Helpful (0)

        How long are the actual mufflers that come with this?

        • The muffler body in the Magnaflow Competition Cat-Back Exhaust is 13" long and 4 inches in diameter.

        Helpful (0)

        Does this catback use the Magnapack mufflers?

        • These would be very similar to the Magnapack mufflers yes.

        Helpful (0)

        Will this cat-back sounds good with a MAC prochamber midpipe?

        • In our opinion, the Magnaflow Competition Cat-Back Exhaust will sound good with a Mac Prochamber mid pipe, however exhaust is subjective.

        Helpful (0)
        Post Your Question

          Customer Reviews (3) Write a Review

          Overall Rating 3.7

          out of 5 stars

          Installation Time:Afternoon

          • Loudness / Volume 4.666667 4.7
          • Exhaust Note 4.666667 4.7
          • Fit & Finish 5 5
          • Bang For Your Buck 4.333333 4.3

          • 1/5

            May 31, 2019


            This product is NOT intended for use with a 3" Mid-Pipe. This product is designed for stock application or equivalent as per Magnaflow directly. It does have 3" main piping but steps down to stock size at the midpipe flange. As always, great customer service from AM, but posting this review in hopes AM will change their description for this product and prevent other customers from dealing with this same issue


            Year: 2003 Submodel: Mach 1

            Helpful (3)

          • 5/5

            July 25, 2018

            It’s alive

            Might result in a ticket or to, but it sounds great!


            Year: 2000 Submodel: GT

            Helpful (9)

          • 5/5

            Installation Time: Afternoon

            February 12, 2016

            New sound!

            This is a beautiful system. A bit pricey but I am happy with the results, well worth it.


            Year: 2002 Submodel: GT Mineral Point, Wisconsin

            Helpful (11)

          Related Mustang Categories