In California, it is illegal to select a catalytic converter for installation based solely on vehicle weight and engine size. The design of these systems often sees an increase in horsepower compared to the factory design of a vehicle. Because stock models try to minimise materials and maximise space, with horsepower as a lower priority.

One issue is that the system can become clogged with dust and debris over time, causing reduced performance. This can be remedied by regularly cleaning the system with compressed air or a soft brush. Finally, it's always a good idea to check for leaks after installation.

Exhaust systems also play a role in reducing noise levels, improving engine performance and reducing fuel consumption. To get the power level up to 785 hp, Shelby installs a Ford Performance supercharger, as well as a new carbon-fiber air intake tube, high-performance fuel injectors, and an aluminum heat exchanger. A Borla (cat-back) exhaust system rounds out the list of powertrain modifications.

A spare set of 19″ Y-spoke alloy wheels is included in the sale, and they are shod with Bridgestone tires. The car is finished in Panther Black Metallic (80U) and features a GXP-specific front bumper cover and rear diffuser as well as a sunroof, fog lights, dual hood scoops, fender vents, and a rear spoiler. Imperfections are noted on the decklid and on a door and are also shown in the gallery. Our expansive inventory of Subaru performance parts ensures your vehicle not only performs at its peak but is also supported by our unparalleled customer service. At SubiSpeed, we understand that upgrading your Subaru is not just about selecting the right parts