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
Win An Eibach Sportline Kit! Enter Daily

Thermal R&D Cat-Back Exhaust (15-17 GT Fastback)

Market Price $1,057.00 You Save 10% ($105.70)
Our Price

$951.30 (kit)

FREE Shipping

  • Item 403883

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, Video & Details

    • Cat-Back Exhaust
    • Cutting-Edge Thermal R&D Helmholtz Technology
    • Improves Horsepower up to 25 RWHP
    • Delivers Augmented Exhaust Tone
    • Made for High-Performance on Street and Track
    • Heavy-Duty 304 Stainless Steel Construction
    • Features Straight-Through Design
    • Sleek Polished Mufflers and Tips
    • Brushed Finished Tubing
    • Tubing Diameter: 3 Inches
    • Angle Tips: 4.5 Inches
    • Basic Installation
    • Lifetime Warranty
    • Fits All 2015-2017 Ford Mustang GT Fastback Models

    Review & Installation Video

    Review & Install Video

    Improved Horsepower. The Thermal R&D Cat-Back Exhaust features cutting-edge Thermal R&D Helmholtz Technology that will effectively improve horsepower in your Ford Mustang GT Fastback by up to 25 RWHP. You’ll love the augmented exhaust tone and high-performance capacity that is perfect for driving your Mustang on the street or the track.

    Steel Construction. Heavy-duty 304 stainless steel is used to manufacture this exhaust kit, which features a straight-through design for improved exhaust flow. The 4.50-inch angle tips and mufflers have a sleek and polished finish. The brushed finish tubing has a 3-inch diameter.

    Basic Installation. Six specialized clamps are included in this Thermal R&D Cat-Back Exhaust to ensure a straightforward installation and proper alignment of the tip. If you plan on expanding on this build and want to run the system to performance headers, then you’ll love the included adapters that will facilitate this additional process.

    Lifetime Warranty. This exhaust comes with a limited lifetime warranty covering craftsmanship defects. Review the warranty information since some limitations may apply.

    Application. The Thermal R&D Cat-Back Exhaust is designed to fit all 2015-2017 Ford Mustang GT Fastback models.

    Fitment: 2015 2016 2017 Details

    MPN# B906-C906

    CA Residents: WARNING: Cancer and Reproductive Harm -

    What's in the Box
    • (2) Polished Mufflers
    • (2) 4.50-Inch Angle Cut Tips
    • (6) Specialized Clamps
    • Adapters
    Installation Info
    Will it fit my Mustang?

      Customer Photos (26) Submit Your Photo

      View All 26 Photos

        Questions & Answers (1)

        1 Top Rated Question

        is this catback as loud the flowmaster outlaws? How loud is it? Comparable? Thank You

        • This will not be as loud as the Outlaws unfortunately. I would say they are closer to the Borla S-Types.

        Helpful (2)
        Post Your Question

          Customer Reviews (7) Write a Review

          Overall Rating 5

          out of 5 stars

          Installation Time:Afternoon

          Installation Cost:0-$100

          • Loudness / Volume 4.285714 4.3
          • Exhaust Note 5 5
          • Fit & Finish 4.571429 4.6
          • Bang For Your Buck 4.571429 4.6

          • 5/5

            Installation Time: Less than 1 Hour

            August 24, 2019

            Awesome exhaust!

            Great sound and absolutely no drone. I love it! Loud enough when needed to grab attention


            Year: 2017 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            August 18, 2019

            Absolutely fantastic!

            If you are looking for an exhaust that flows great and doesn't sound obnoxious, this is it! I have listened to countless sound clips and seen tons of different Mustangs with differnet exhausts and many have a tendency to be way too loud or raspy. The best thing is there is ZERO DRONE. I had a Magnaflow resonated X-pipe and muffler delete for just over a year and the drone between 55 - 60 mph in 6th gear was deafening. I can now have a conversation with someone while in the car.


            Year: 2015 Submodel: GT

            Helpful (1)

          • 5/5

            May 09, 2019

            Great sound!

            It was quick and easy to install. I absolutely love the sound!


            Year: 2016 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Afternoon

            November 16, 2018

            Probably best sounding I've heard

            The few sound clips online doesn't do this exhaust justice. Probably one of the best I've heard. Nice low rumble but maybe a little raspy in wide open throttle in the high RPMs. Maybe 2 hours or so to install.


            Year: 2015 Submodel: GT

            Helpful (6)

          • 5/5

            Installation Time: Less than 1 Hour

            September 03, 2018

            Love It!

            ABSOLUTELY love this exhaust. Couldn't be happier. Install was a breeze and the sound is amazing!


            Year: 2015 Submodel: GT

            Helpful (6)

          • 5/5

            Installation Time: Shop Install

            Installation Cost: 0-$100

            May 01, 2018

            Excellent System

            The exhaust is fantastic quality. Welds are done expertly and every piece looks to be designed with a purpose. The tone on the exhaust is very aggressive and deep without being overwhelmingly loud in the way my previous system (Roush axle back with H-pipe) was. When you want it to rip however the exhaust comes to life and roars. On downshift you get a nice note and letting the RPMs come down gives some nice crackle. It is awesome that the exhaust has 0 drone at highway speeds, as it is by design with the helm holtz chamber. For the price, especially compared to other cat-back systems, it is incredibly hard to beat. Youtube videos do not do this justice.


            Year: 2016 Submodel: GT

            Helpful (14)

          • 5/5

            Installation Time: Afternoon

            March 05, 2018

            American muscle

            This website has all the upgrades and style you want. Not overpriced prices either. I’ve been using American muscle for a while now and my mustang is already built


            Year: 2017 Submodel: GT

            Helpful (10)

          Related Mustang Categories