Subaru WRX STI

The Subaru WRX STI is a variant of the Subaru WRX sedan produced by in-house tuning company Subaru Tecnica International between 2014 and 2021. It succeeded the Subaru Impreza WRX STI. Production of the WRX STI concluded after its first generation, there are currently no plans for a VB WRX STI. STI also offers many factory-backed accessories usually available from dealerships, and accented in STI's signature cherry blossom, a tribute to the iconic tree of the same name from the brand's homeland of Japan.

First Generation (VA; 2014-2021)
The VA WRX STI was released in 2014 alongside the VA WRX. It featured uprated brakes, the famous Subaru Technica International tuned EJ257 4-cylinder engine, an uprated 6 speed manual transmission, along with a unique body kit and spoiler. Interior upgrades include an STI-exclusive gauge cluster, shifter knob, and other unique touches, including Recaro bucket seats in certain models. The WRX STI for the most part featured a red accented interior, over the WRX's black and grey.

Starting with the MY2016 update, the WRX STI gained fluorescent green brake calipers, which was a hit among the Subaru community, and is now an easy identifier of the WRX STI.

In 2020, Subaru announced they would be phasing out the WRX STI along with the EJ257, the last variant of the EJ engine, with the release of the VB series WRX in 2021. Subaru introduced the STI WRX EJ25 Final Edition, based on Subaru's flagship STI Spec R. The EJ25 Final Edition features a range of upgrades including BBS 19” gold forged aluminium wheels, silver Brembo calipers, black door mirror covers, front grille pinstripe in STI cherry blossom, Final Edition engine cover plate, and numbered EJ25 Final Edition badge. Only 75 were produced for markets across the globe.

Second Generation (VB; 2021-)
There is no official VB WRX STI available, nor are there plans for such a model to be released. Instead, Subaru is has introduced several trim levels of WRX with 'tuning by STI' and STI offers many accessories for the second generation WRX such as lip spoilers, exhaust tips, shifter knobs, and many other options depending on region.

Especial Edition (2024) WRX S4 STI Sport
The 2024 Subaru WRX S4 STI Sport is a limited edition model, painted in a model-exclusive Offshore Blue Metallic colour. Externally, the model gains an STI body kit and 19-inch BBS forged wheels. Inside, adjustable Recaro front seats featuring STI logos as well as details in silver stitching and suede material on the central console and dashboard are added. Performance-wise, the model retains the 271-horsepower turbocharged engine shared with other WRX models, complemented by more robust stabilizer bars and an enhanced transmission cooler.

The Subaru WRX S4 STI Sport is offered through a lottery system in Japan only for approximately price of $43,000.

Engines
The only tuned-by-STI engines that have been in the standalone WRX STI are the EJ257 (Export) and EJ207 (JDM only) specifications of the Subaru EJ engine. (Although earlier Impreza-based models were also fitted with the EJ22G Boxer Turbo)) The highest output model of EJ25 ever produced, producing up to 341 hp (346 PS; 254 kW) at 6,400 rpm and 330 lb⋅ft (450 N⋅m) of torque at 3,600 rpm, in the 2019 STI S209. One of the main reasons the STI was retired in the VB WRX is the adoption of the Subaru Global Platform, which was not engineered for the EJ, only using the FA and FB engines, of which STI does not produce a tuned variant of currently.