Borla 13-14 Mustang Shelby GT500 GT 5.8L V8 RWD Dual Split Rear Exit ATAK Exhaust Rear Section OnlyBorla 13 14 Mustang Shelby GT500 GT 5. 8L V8 RWD Dual Split Rear Exit ATAK Exhaust Rear Section Only Since mid 1964, Mustang has always been about muscle, looks, and loads of customization options. Borla's lineup for the Mustang GT and Shelby GT500 lives up to this legacy, with systems to meet a wide variety of performance goals and budgets. For soundaholic Mustang GT drivers who won't settle for anything less than unbridled performance with a pure,