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Flowmaster American Thunder Cat-Back Exhaust (99-04 Cobra)

Item 18409
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Market Price $607.99 You Save 21% ($124.73)
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Ship to: Ashburn - 20149
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    Features & Details

    • Aggressive Flowmaster Sound.
    • 40 Series Mufflers.
    • 3" Polished Stainless Steel Tips.
    • Mandrel-Bent Tubing.
    • Durable Aluminized Steel Construction.
    • Fits 1999-2004 SVT Cobra Mustangs.
    Flowmaster Sound .The Flowmaster American Thunder Cat-Back exhaust system with its mandrel bent tubing will greatly improve your 1999 to 2004 SVT Cobra Mustangs exhaust flow for an increase in power, and their included 40 Series Mufflers will improve your exhausts sound for a deeper throatier muscle car exhaust note.

    Quality Construction. Constructed from mandrel bent 2.5" 16 gauge aluminized steel tubing for it's corrosion resistant properties the Flowmaster American Thunder Cat-Back features their 40 Series chambered mufflers with 3.0 " diameter OEM style polished stainless steel tips for great muscle car looks and sound.

    Fitment. This Flowmaster American Thunder Cat-Back exhaust system is specifically designed to fit the 1999 to 2004 SVT Cobra Mustangs with Independent Rear Suspension (IRS) for both impressive looks and sound.

    Fitment: 1999 2001 2003 2004 Details

    MPN# 17248

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    Hardware included:
    • (2) Clamps
    • Installation Instructions
    Installation Info
    Tech Specs
    Cat-Back Exhaust Specifications
    Piping Material: Aluminized Steel Tip Material : Polished Stainless Steel
    Piping Size: 2.5" Tip Size: 3.0"
    Muffler Type: Chambered Fitment: 1999-2004 SVT Cobra Mustangs
    Will it fit my Mustang?

      Customer Photos (6) Submit Your Photo

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        Questions & Answers (3)

        3 Top Rated Questions

        would this fit on my 97 svt cobra,?

        • This exhaust is for Mustangs with Independent Rear Suspension. If your 97 Cobra does not have an IRS swapped in place for its stock Solid Rear Axle, then this will not properly fit your car.

        Helpful (1)

        What's the exhaust diameter size?

        • The exhaust uses 2.5-inch mandrel-bent tubing.

        Helpful (0)

        would it fit on my 97 svt cobra?

        • The Flowmaster American Thunder Cat-Back Exhaust (99-04 Cobra) is specifically designed to fit the 1999 to 2004 SVT Cobra Mustangs. This will not fit a 97 Cobra.

        Helpful (0)
        Post Your Question

          Customer Reviews (16) Write a Review

          Overall Rating 4.4

          out of 5 stars

          Installation Time:Afternoon

          • Loudness / Volume 4.090909 4.1
          • Exhaust Note 4.909091 4.9
          • Fit & Finish 4.363636 4.4
          • Bang For Your Buck 4.727273 4.7

          • 5/5

            Installation Time: Less than 1 Hour

            October 13, 2019

            99-04 Mustang Cobra Cat Back

            Great Deal! Easy to install, No problems! It took me 45mins to install! And the sound is classic flowmaster!


            Year: 1999 Submodel: Cobra

            Helpful (0)

          • 5/5

            Installation Time: Afternoon

            May 16, 2018

            Flowmaster update

            Changed from Gibson to Flowmaster and the difference is remarkable. Deeper more throatier tone and sounds more aggressive.


            Year: 1999 Submodel: Cobra

            Helpful (3)

          • 4/5

            Installation Time: Afternoon

            April 03, 2018

            All American sound

            Love the throaty sound. Could be louder at higher rpms.


            Year: 2004 Submodel: Cobra

            Helpful (3)

          • 5/5

            Installation Time: Less than 1 Hour

            August 18, 2017

            Ayyyyy Lmao

            I bought this for a Foxbody that I swapped an IRS into. FYI if you buy this for the same reason you will have to shorten the section of pipe that connects to the mid pipe.


            Year: 2014 Submodel: GT

            Helpful (4)

          • 1/5

            July 07, 2016

            Fitment is horrible, sounds good

            Right side muffler touches my differential weight, one pipe sticks out farther then the other by half inch. To top it off I called and left a voice mail with American muscle to complain and no one called me back. I guess I will go to lethal performance next time


            Year: 2003 Submodel: Cobra

            Helpful (4)

          • 5/5

            Installation Time: Less than 1 Hour

            August 31, 2015

            Flow Master

            Great exhaust, nice sound to it. Quite until you get on it after 3K. I liked how easy it bolted on. The only thing I didn't like was that they didn't provide exhaust clamps for the catback. Had to go to Autozone to purchase 2 1/2 inch clamps. Other than that I'm happy with the exhaust. No drone inside as well.


            Year: 2003 Submodel: Cobra South Bay, Ca

            Helpful (4)

          • 3/5

            Installation Time: Afternoon

            June 01, 2015

            Great sound, fitment total package 3 stars

            Great sound for sure, just what I wanted. But I was disappointed when it arrived to find that unlike the pictures on the product, the system comes in two pieces per side that have to be connected with muffler clamps. That was some extra fiddling during installation and contorting to get it all aligned right, and now from the rear of my car I can see those muffler clamps under there. I can't get it welded either because fitment in getting them on was not as simple as bolting in, I had to slide the rear most section in the back mount, tip the connection from the xpipe down, and barely made them come together to get on, so if I got it welded, it would be in there for good. Overall a nice product with a nice sound, but was disappointed in fitment.


            Year: 1999 Submodel: Cobra

            Helpful (6)

          • 5/5

            Installation Time: Afternoon

            May 09, 2013

            Cat-back installation (Flowmaster) on 2003 SVT Cobra

            Fortunately, I have a lift. Removal took longer than assembly! Everything was very simple and foolproof. It brought the little Cobra to life! Didn't need the stainless as car is, (and will remain) in Texas. Hats off to your team!


            Year: 2003 Submodel: Cobra

            Helpful (5)

          • 4/5

            Installation Time: Less than 1 Hour

            June 16, 2012

            not to shabby for the money spent!!!

            i was gonna go with slp1's cat back then thought back to when i had flowies on my old s10 and decided to give em another shot, and glad i did!! they were pretty easy to install and took me about an hour up on jack stands. the loudness isn't as loud as i thought it would be but still sounds amazing tho. at first they were kinda quite but after a couple weeks they seemed to get louder and louder so im pretty happy with them. they got this deep rumble to em thats simply awesome, they almost dont sound like flowmasters signature sound, more like glasspacks, but i think thats because of the four cats i got. all that stuff is still stock. the shinney tips give it a good look from behind too. it took two days for me to recieve them by ups as promised. if you want a good sound, this is the way to go for sure!!!!


            Year: 1999 Submodel: Cobra New Florence, PA 15944, USA

            Helpful (4)

          • 5/5

            Installation Time: Afternoon

            February 24, 2012

            flowmaster exhaust

            these fit really well, had no problems putting them on but when i started to tighten the nuts the muffler twisted down a little so i put a small jack under the muffler so it wouldnt twist down other than that i had no problems.


            Year: 1999 Submodel: Cobra Yukon, OK

            Helpful (5)

          • 4/5

            Installation Time: Shop Install

            January 29, 2012

            Great Upgrade to Sound

            I have a 2003 SVT Cobra that the original owner put "glasspacks" on and the sound was annoying for me. I finally put the Magnaflow on and it sounds much healthier! The fit,price and product is always as advertised. Thanks.


            Year: 2003 Submodel: Cobra Tacoma,WA.

            Helpful (6)

          • 5/5

            Installation Time: Less than 1 Hour

            October 06, 2011

            Flowmaster Catback

            I've had flowmaster on 3 of my previous mustangs and just purchased another catback for my 03 Cobra. I've heard all the other competitor's catbacks and I'm still a fan of flowmaster. The sound is aggressive without being over the top. When I think of what a muscle car should sound like, flowmaster nails it.


            Year: 2003 Submodel: Cobra Paso Robles, CA

            Helpful (6)

          • 5/5

            June 11, 2011

            American Thunder Caback for 99-04 Cobra

            My 03 Cobra sounds like a beast. It turns head when people hear me coming or leaving. I have Pypes O/R X pipe also which makes the tone even more deeper. The fitment of the catback was nearly perfect only took a couple of hour to install in my driveway.

            Bear Miller

            Year: 2003 Submodel: Cobra

            Helpful (4)

          • 5/5

            June 10, 2011

            Flowmaster Cat Back

            I have the flowmaster cat back 40 series along with the MAC off road prochamber installed on my 2001 Cobra and its great! I love the sound.. very very deep and loud if thats what you are looking for.. maybe a little difference in throttle response and horsepower but mainly great for the true cobra sound. I would suggest this for anyone with a V8 mustang.. classic product for the mustangs. Installation took me about an hour in my garage with jack stands. all bolt on great system.

            Tim Tourdo

            Year: 2001 Submodel: Cobra

            Helpful (6)

          • 5/5

            July 26, 2010


            Sounds great. Was easy to install and has great fitment.

            Darren R

            Helpful (9)

          • 5/5

            June 20, 2010


            Sounds great with O/R MAC Prochamber

            Greg Sapp

            Helpful (13)

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