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Flowmaster American Thunder Cat-Back - Stainless Steel (99-04 Cobra)

Market Price $689.99 You Save 12% ($79.65)
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  • Item 18448
  • MPN# 817248

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    Features & Details

    • Aggressive Flowmaster Sound
    • 40 Series Mufflers
    • 3" Polished Stainless Steel Tips
    • Mandrel-Bent Tubing
    • 409 Stainless Steel Construction
    • Fits 1999-2004 SVT Cobra Mustangs
    Flowmaster Sound. Give your SVT Cobra that unmistakeable Flowmaster sound with a nice power boost by installing a American Thunder catback Exhaust system. Featuring mandrel bent tubing this Flowmaster system will improve exhaust flow for an increase in power, and the included Super 40 Series Mufflers will improve your exhausts sound for a deeper throatier muscle car exhaust note.

    Quality Construction. Constructed from mandrel bent 2.5" 409 stainless steel tubing for it's corrosion resistant properties the Flowmaster American Thunder Cat-Back features their 40 Series chambered mufflers with massive 3.0" diameter OEM style polished stainless steel tips for great muscle car looks and sound.

    Application. This stainless steel 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 impressive looks and great sound.

    Fitment: 1999 2001 2003 2004 Details

    CA Residents: Warning: California's Proposition 65

    What's in the Box
    • (2) Muffler assemblies
    • (2) Over axle pipes
    • (2) Exhaust Tips
    • (2) Clamps
    Installation Info
    Tech Specs
    Cat-Back Exhaust Specifications
    Piping Material: 409 Stainless 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?

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    Customer Reviews (12) Write a Review

    Overall Rating 4.9

    out of 5 stars

    Installation Time:Afternoon

    Installation Cost:$100-$250

    • Loudness / Volume 4 4
    • Exhaust Note 4.666667 4.7
    • Fit & Finish 4.5 4.5
    • Bang For Your Buck 4.75 4.8

    • 5/5

      Installation Time: Less than 1 Hour

      February 26, 2018

      Paired with a BBK x pipe

      I am really happy with the sound from this cat back. I cannot image having a louder kit.


      Year: 1999 Submodel: Cobra

      Helpful (2)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: $100-$250

      November 15, 2017

      Sounds like a Cobra

      Exhaust sounds really good not too loud sounds good while idling, just enough to be noticed, it fit really well on my 99 Cobra and looks good.


      Year: 1999 Submodel: Cobra

      Helpful (4)

    • 5/5

      Installation Time: Less than 1 Hour

      September 24, 2017

      Great Exhaust Note!

      Gave my mustang that clean classic muscle car sound. Sound difference is definitely noticeable. Doesn't sound muffled or restricted. Has a nice open and throaty sound to it. I would recommend changing out your factory H-Pipe with this exhaust set up. Gave it better sound and also gave it a lot more pep when I got rid of the factory H-Pipe. Fitment was alright. Had to pull some of the exhaust hangers into the right position, not hard to do.


      Year: 1999 Submodel: Cobra

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      May 18, 2016

      Great sounding exhaust!

      I was pleased the way they packaged the product as well as the quality. The flowmasters bolted right on and was an easy install ( I did mine on my lift) one cannot beat the sound of the flowmasters in my opinion all around easy fit great sound and great product!


      Year: 2003 Submodel: Cobra

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      August 06, 2014

      Its Flowmaster

      Replaced a 3" mac cat back off my 03 cobra with this and the sound and look are big improvement. Had to take the differential weight off due to passenger pipe hitting it but have not noticed any difference in driveline vibrations so I guess its ok, so -1 star for that.


      Year: 2003 Submodel: Cobra Louisville, KY, USA

      Helpful (4)

    • 5/5

      Installation Time: Afternoon

      May 23, 2014

      Aggressive but not Overbearing

      I was looking for a little deeper sound, without annoying the neighbors (well, maybe a little). This catback provided what I was looking for. A little deeper sound to make it a little more like the Cobra it is, without it being too annoying for a car I drive on a regular basis. Maybe it'll help with the "Is that even a real Cobra?" I get for having a '99... Install wasn't too bad, the bolt spacing on the connection to the cats didn't have as much tolerance as I would have liked. I also had one hanger on the passenger side that was kind of stubborn to get up into, but in the end I was able to get everything lined up well. I'm a novice so take that into account, as my minor troubles may have just been chalked up to inexperience. I also have a new appreciation for the IRS this car has, as there was no up and over the axle to worry with. I'm happy with the result and got the sound I was looking for.


      Year: 1999 Submodel: Cobra Maryland, USA

      Helpful (3)

    • 5/5

      Installation Time: Shop Install

      Installation Cost: 0-$100

      May 02, 2014

      Great sound!

      Installed on a 2001 cobra, sounds REALLY good. would recommend this product to any mustang owner. there is nothing like the sound of the 2 chamber flowmaster, gets your head turning!!


      Year: 2001 Submodel: Cobra Connecticut, USA

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      August 26, 2013

      Awesome product!

      This was a great install. The sound was amazing! We were happy with the quality of the product. To top it off, we received a rebate from Flowmasters. This Cobra roars to life with our new pipes! We love it!


      Year: 2004 Submodel: Cobra Eau Claire, WI, USA

      Helpful (3)

    • 5/5

      Installation Time: Afternoon

      July 24, 2013

      American Thunder

      All in all the product is great. I selected afternoon for install time based on whether or not you have a lift. I did it in my driveway with jackstands and it took the better part of an afternoon. Farthest bolt to the passenger side off the header is a doosie. But if you only ordered the cat back this won't be a problem for you. I installed this cat back with a Magnaflow carted tru-x pipe. NY compliant. Once that bolt was free the rest was fitting it in and leveling it out to tighten it up. I would recommend this to anyone who wants to hear the true beauty of owning a piece of American Muscle. 2003 Mineral Grey Vert Cobra


      Year: 2003 Submodel: Cobra NY

      Helpful (4)

    • 4/5

      Installation Time: Afternoon

      July 03, 2013

      Fit and finish on this catback was great!

      Received this product quickly, took my time installing the catback in my garage, and was very easy. Have plenty of clearance for the exaust and no rattles or leaks. Just keep in mind that this hangs lower than stock, car is not lowered. Very happy with product.


      Year: 1999 Submodel: Cobra South Chicago suberbs

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      June 02, 2013

      Flowmaster American Thunder Catback - Stainless Steel (99-04 Cobra)

      I am pleased to say that the product installed exactly as described in the directions I down loaded from your site. I indicated "afternoon" but it was only a little more that an hour. We did use a torch to heat nuts to remove the old pipes, but were able to reuse the bolts and nuts to install the new pipes. I am very satisfied with this product and the installation.


      Year: 1999 Submodel: Cobra Chilton, WI 53014, USA

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      November 09, 2012

      Flowmaster American Thunder Catback - Stainless Steel (99-04 Cobra)

      This exhaust fits good and sounds good, but could be slighty louder. I would buy it again.


      Year: 1999 Submodel: Cobra Williamsport, PA, USA

      Helpful (3)

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