Per expectations, the STI takes the already improved WRX formula and adds extra power and grip. The 2.5-liter turbocharged boxer four-cylinder engine carries over with 305 hp and 290 lb-ft of torque, or just slightly more than the top-shelf Mitsubishi Lancer Evolution. It's matched to an improved six-speed manual gearbox that our test of the standard WRX shows to be a slick, quick-shifting box with short, crisp throws.
From the transmission, power goes to Subaru's Driver Controlled Center Differential, which gets three performance modes and six manually controlled differential settings. All those electronic settings are augmented by a mechanical limited-slip feature that defaults to a 41/59 front-rear torque split. Power is handled at the front axle by a helical gear limited-slip differential and at the rear by a Torsen torque-sensing electronically controlled limited-slip differential.
On top of all that is Subaru's new Active Torque Vectoring software, an upgrade to the standard Vehicle Dynamics Control stability- and traction-control system. The active torque vectoring, like on the standard WRX, brakes the inside wheel and sends torque to the outside wheels during cornering. Vehicle Dynamics Control, meanwhile, can be fully switched off.
At the ground, larger 18-inch forged BBS wheels are wrapped in wider 245-series summer performance tires for even more grip than the already Velcro-like WRX. Behind the gold shoes are big Brembo four-piston front and two-piston rear calipers. Brake rotors are 13 inches and 12.4 inches at the front and rear, respectively. Unlike the standard WRX, the STI's front wheels are still actuated by a hydraulic power-assist rack rather than electric.
2015 Subaru WRX STI First Look
Reviewed by BlogCarShow
Published :
Rating : 4.5
Published :
Rating : 4.5
