2007 SUBARU WRX AND STI RESEARCH PAGE Research WRX, WRX Limited, STI, STI Limited prices, options, specifications, colors, links. CARS101.COM homepage: Outback specs: Impreza ... STI, STI LImited sedan: SPT Performance Exhaust System #SOA8377900 SPT High Flow Air intake System #SOA8431000. Cat-Back Exhaust, fits Subaru WRX/STI 2015-2021. Model: MMEXH-WRX-15. Installation Difficulty. Regular Price: $1,237.25. Sale Price. $1,114.95. Direct fit for the 2015-2021 Subaru WRX/STI. Dyno-proven maximum gains of up to 9 whp and 8 wtq and peak gains of up to 4 whp and 3 wtq using 93 octane fuel while maintaining safe AFRs on the stock tune .... 8.2 : 1. Horsepower. 300-341hp. Torque (lb-ft) 290-330 lb-ft. The EJ257 is unique in its flat four cylinder design. Few other manufacturers use this engine layout. It’s part of what gives many Subaru’s a unique sound. Anyways, the 2,457 cc displacement rounds up to 2.5 liters. The ’08 STI, a wagon only and equipped with 12 more horsepower, no additional torque, and way more buttons, asks for $35,640. Another $2000 is demanded for the look-at-me 18-inch BBS wheels and.