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  See more parts for your Ford Mustang GT


$509.99 Sale:$469.99


Model #4101

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Shopper Award

This product is for Racing Competition only and is not legal for use in highway or street vehicles or other non-racing competition off-road vehicles.

Purchasing this product requires you to sign our Vehicle Compliance Waiver here.


  • Unique Internal Power Valve Allows Fine Tuning of Sound and Power Level
  • Change From One to Three Chamber Muffler by Turning a Wrench
  • Large 2.75" Mandrel Bent Tubing for Maximum Flow
  • 8-10 Decibel Range Difference
  • 4" Stainless Steel Tips
One-of-a-Kind Adjustable Axle Back
The BBK Varitune Axle Back Exhaust Kit for 2011-2014 Mustang 5.0L offers full tuning ability with BBK's patented adjustable power valve. That's right, these unique systems come complete with two patented tunable Varitune performance mufflers engineered with high-flow, direct fit 2-3/4" tubing and hardware for an easy bolt on installation. Each system also includes a pair of stylish 4" stainless tips to deliver good looks in addition to maximum performance.

Adjustable Mufflers?
These American designed and built performance mufflers are the first of their kind in the aftermarket fully adjustable performance mufflers that can be adjusted for sound and horsepower by simply moving the adjustment screw in or out from underneath the car! BBK Varitune performance mufflers utilize a unique internal power valve. When in the closed position the valve blocks the exhaust flow, forcing it through all three chambers of the muffler for a classic mellow sound. When in the open position, the valve opens the exhaust flow allowing it to take the path of least resistance, acting more like a straight-through muffler for an aggressive throaty exhaust note.

BBK Varitune exhaust kits are engineered and built with large 2-3/4" CNC mandrel bent aluminized tubing for unrestricted exhaust flow. These Mustang Axle Back kits are direct fit and include all hardware required for a true bolt on installation. No cutting or welding is required.

Fits2011-2014 Mustang 5.0L GT or Boss 302

Other Part Numbers:
BBK #bbk4101

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Vehicle Engine Notes
Ford Mustang GT

Who is BBK Performance?

BBK Performance is an aftermarket company that was established in 1988. They specialize in creating performance parts for muscle cars and was founded by Brian and Ken Murphy. They were the first to design and manufacture an aftermarket air intake system and performance throttle bodies for the fuel-injected 5.0 Mustang and TPI Camaros. 

Today they have expanded their offering to a wider range of vehicles catering to other modern cars and trucks as well and with more performance parts such as exhaust systems, suspension parts, and more.

Experienced Manufacturer

BBK has been developing and manufacturing performance parts for over 20 years and has used that gathered knowledge to improve their products. Their parts are considered as high standards and are comparable, if not better to the Original Factory parts.

Ease of Installation

The company ensures that its clients would have a hassle-free experience from purchase to installation. Hence, all their products are a direct bolt on to the vehicle. It also comes with a comprehensive installation manual and all the necessary hardware needed for the install.

Continuously Growing

The company initially started in a 1200 square feet building in Southern California. Today, they have grown to a 200,000 Sq ft facility that houses their own research and development center with a built-in dynamometer and state-of-the-art manufacturing pieces of machinery. The company also employs the industry's leading craftsmen, making sure that their customers would only get the best product for their money.

Purchase BBK Products at Vivid Racing

If you are in search for top-notch performance parts for your vehicle, then check out BBK Performance. They carry a long list of parts that would fit most modern vehicles today. Visit Vivid Racing and see what BBK has to offer. You will surely find the right parts for your specific needs.

  1. All BBK products are warranted against any defect in materials or craftsmanship for a period of one year from the date of purchase. These terms apply as long as it has been established that the product in question was installed and used in accordance to all BBK guidelines and was not used for racing or competition purposes.
  2. BBK Performance will not be held responsible for any consequential or incidental damages incurred during installation and will not be held responsible for any incidental or labor charges on any products that are defective, warranted, damaged, or parts that were purchased incorrectly. PLEASE NOTE SOME PRODUCT SPECIFICS ARE NOT COVERED BY WARRANTY - SUCH AS ELECTRONICS, COATINGS/FINISHES, BUSHINGS AND HOSES ETC. - RUST/RUSTING IS NOT COVERED BY WARRANTY.
  3. If your warranty issue is after the stores replacement or return policy (usually 30 days) - you will need to contact the BBK Performance warranty department directly via e-mail to request a warranty return number and warranty approval.

    BBK will e-mail you a request for a copy of the original product receipt and also a product questionnaire to fill out to help us determine why the BBK product has caused a warranty issue.

    The original receipt must show the original date of purchase and it must also be supplied via e-mail along with the product questionnaire or the warranty is null and void. If your part is approved for a warranty return, you will be issued a Return Goods Authorization number (RGA) and the BBK return address to send the part back for inspection.

    Please be sure to include your name, return address and contact phone number in the box when you ship the part back for identification purposes. PRINT OFF THE RETURN APPROVAL FORM WE E-MAIL TO YOU AND PUT IN THE BOX IS THE SIMPLEST WAY AS IT CONTAINS ALL YOUR INFORMATION INCLUDING THE RGA #.


    The return authorization number (RGA) must be clearly marked on the outside of the package in order for our warranty department to process the item. If no RGA is visible - or if package is sent collect freight - package will be refused and sent back to you at your expense.

    Upon receipt of your warranty return it will be inspected by our BBK warranty engineers. If your BBK Product is determined to be defective and covered by our warranty, the item will be immediately repaired or replaced at no cost to the consumer. PLEASE NOTE: WE DO NOT ISSUE ANY KIND OF PRODUCT REFUNDS ON ANY WARRANTY RETURNS; THIS INCLUDES SHIPPING AND LABOR CHARGES.
  4. ALL Warranty Returns are processed within 2-3 days of receipt and you will be notified of the status of your return - please refer to your RGA # you were issued in all communications with us -
  5. All warranties are valid from the original date of purchase only - they are NOT pro-rated based on a warranty part - replacement or repair.
  6. BBK Performance is not responsible for product fitment, print, Internet typographical and photographic errors.
  7. BBK Performance reserves the right to charge a minimum 15% restocking fee for all non-defective RGA requests or returned items purchased directly from the website in error.

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