Changes in the engine compartment consist primarily of a fourth generation Legacy GT style intake manifold and intercooler. The TD04 turbo remains from the previous generation, however it has been adjusted to fit the new intake design.
Power output consists of 169 kW (227 hp) and 320 N·m (236 lb·ft) from its 2.5-liter engine. It was offered in either a five-speed manual, or 4 speed automatic. The five-speed manual transmission was changed to the same found in the fourth-generation Legacy GT. The rear limited slip differential has been discarded in exchange for the new VDC (Vehicle Dynamics Control) system. The weight of the car also has been reduced and gives the WRX a 0 to 100 km/h (0 to 62 mph) time of 5.8 seconds.
The EJ255 engine received an output boost to 198 kW (265 hp) and 331 N·m (244 lb·ft) of torque by swapping the previous TD04 turbocharger to an IHI VF52. This lent to the car now achieving a 0–60 time of just 4.7 seconds, as tested by Car and Driver. In addition, the updated model received altered springs/struts, sway bars, and Dunlop summer tires to improve handling.