GT4-S Mustang

  • 650 Nail You to the Seat Horsepower
  • 650hp Supercharged 5.0L 4V TiVCT Coyote Engine
  • Remarkable, well-balanced, yet "wicked fast"
  • GT4-S Performance Package
  • Designed to complement and support massive power
  • Incredible power that's remarkable with unbelievable acceleration
  • Civilized in day to day driving
  • Special version available for 2013/14 GT’s with SelectShift automatic


The Kenny Brown GT4-S is a premium performance Mustang with 650 “Nail You to the Seat” supercharged horsepower, specifically designed with speed and agility in mind. The GT4-S easily outpaces the Shelby GT500 at track days, but the awesome power is only part of the performance equation.

It's lighter, quicker, and more responsive than a Shelby GT500, or even the fabled Super Snake. As with all Kenny Brown Mustangs, there is an artful balance of power, grip, handling, and braking in the overall performance package.  A large part of that equation is the critically acclaimed AGS 4.0 Advanced Geometry Suspension System which is the “secret sauce” in the car's incredible handling and confidence-inspiring driving characteristics.  But it doesn’t stop there as additional upgrades include bigger brakes, wider wheels, large sticky tires, high-flow exhaust, and a host of other select upgrades to balance out the wickedly fast GT4-S Mustang.  And as always – Kenny offers a plethora of performance options to truly make it your very own bespoke creation.

The new 2013 Kenny Brown GT4-S Mustang is the most powerful to date with a 0-60 acceleration time and sheer cornering grip that rivals the industry's best.  Never in the company's history has such a potent Mustang been unleashed on the general public, and we have Ford's awesome new 5.0L TiVCT powertrain to thank for that.

2013 Kenny Brown 605hp GT-4Sa Mustang Automatic - Two Pedals of Pure Joy

Yes, a super-fast, supercharged GT4-Sa Mustang with an Automatic. Until now all supercharged Kenny Brown Mustangs have come only with manual transmissions. But the new 6-speed automatic transmission in the 2013 Mustangs has changed the equation, and Kenny’s thinking, providing you all the excitement with just two pedals.

The GT4-S automatic Mustang is designed primarily as a wicked fast street car, but it feels right at home on the track. With a healthy 610 supercharged horsepower and all the carefully selected equipment that makes it a dream to drive. The automatic combined with traction control make it a brilliantly quick, yet amazingly civil car just driving around town. This is the kind of Mustang that you can seriously spank a Viper with at the toll booth grand prix - with a cup of coffee in your hand. If you're feeling really sporty, click the traction control into Sport Mode, drop the shifter into Select, and unleash the beast. The SelectShift lets you select gears up and down manually with a touch of a button, and the traction control in Sport Mode gives you tire smoking capability, but you had better be hanging on to the steering wheel and forget the coffee because this speed monster demands respect.

Kenny Brown GT4-S Mustang conversions are available for 2011-2014 Mustang GT’s with the 5.0L Coyote engine, BOSS 302 Mustangs.


Content based on a 2012-13 Mustang GT with the Track Pack option. Content varies slightly with stock GT, V6 or GT500.

We offer a free design service with many options to further customize your Kenny Brown Mustang to make it your own. It's on the house - extra service and advice with Kenny involved from the start to oversee your project. We can help as little or as much as you would like.  You'll see and we can create a plan that meets your goals and budget… and when you're ready, we'll bring the project to life.  Our design experts can work with you by phone, online or by visiting our Performance Center.

  • Supercharged Engine - 650 HP (Automatics 610 HP)
    • Vortech Supercharger System
    • Cold Air Intake
    • Air-to-Air Intercooler
    • Custom 92 octane Street Calibration

  • Upgraded exhaust w/high-flow mufflers

  • Performance Shifter

Rear End
  • Boss 302 Aluminum Differential Cover
  • Torsen differential
  • 3.73:1 Final drive ring & pinion

  • HD aluminum radiator
  • Positive flow radiator ducting
  • Oil Cooler

High Performance Brakes
  • Brembo GT Track Pack Mustang calipers front & OEM Rear
  • Rear 14” Rotor Upgrade
  • KB Select high-performance brake pads front & rear
  • High-temp brake fluid

Wheels & Tires
  • Performance Wheels -- 18”x10” front and 18”x11” rear
  • Max-Performance tires  295/35/R18 front and 315/30/R18 rear

Chassis Support
  • KB Jacking Rails
  • KB Extreme Matrix Chassis Support System

  • Kenny Brown AGS 4.0 Street Sport Suspension
    • Advanced Geometry Suspension System
    • Adjustable front Sway Bar

Track/Sport Springs and Shocks
  • KB Spec Street Sport Shocks
  • KB selected spring rates
  • Adjustable ride height

  • Side Skirt Splitters
  • Paul Brown Racing Sport Rear Spoiler
  • Custom Graphics

  • Driver’s left foot dead pedal
  • RECARO GT Track Pack Mustang Seats

Serialization & Graphics
  • Dash plaque & Under hood production plaque
  • Special exterior GT4-S graphics package
  • Log Book, set-up, history & maintenance info

  • Please call our Performance Center to talk with one of our design pros about all the options available to further custom tailor your Mustang for your specific requirements.  Call 317-396-2768 or email to


2013 Kenny Brown GT4-S Custom Conversions Starting at $ 29,950

Final cost will vary as each Kenny Brown GT4-S is hand build, bespoke with content specific to the individual’s needs and budget.