The WRX S4 tS gets some extra oomph from Subaru Tecnica International (STI).
Subaru Wrx S4
Subaru showcases a range of upgrades in the forms of the XV Sport, Legacy B4 Blitzen, Levorg S and WRX S4 Prova concepts at the 2015 Tokyo Auto Salon.
A month after originally teasing it, Subaru is finally unveiling its WRX S4 model for Japan. It's a bit more than just a plush take on the sport sedan, because Subaru is fitting a more powerful version of the 2.0-liter, turbocharged boxer four-cylinder engine than we get on these shores.
The Subaru WRX range is growing just a little bit larger, at least in Japan, with the automaker's teasing announcement of a new version called the S4. Unfortunately, the company is keeping details about its latest all-wheel drive sport sedan a closely guarded secret for the moment.