Sadly, it won’t be a mass-production model nor will it actually be sold outside of Japan. Instead, like the eight previous STI Complete Cars (or S models), it will be limited to just a 500-unit production run.

Subaru says the WRX STI S210 incorporates technology and knowledge it cultivated in the Nürburgring 24 Hours Race. It still uses the WRX’s 2.4-liter FA24 Boxer engine, but thanks to a revised air intake, turbo ducting, and exhaust, power is up to an even 300 horsepower (at 5,700 rpm)—up 25 horsepower from the standard WRX. Meanwhile, torque is up to 375 Nm—up 25 Nm from stock. Even more impressive, that torque is realized through a wider power band (2,000 to 5,600 rpm).

Oddly enough, despite the added grunt, Subaru and STI decided to retain the WRX’s standard Subaru Performance Transmission (aka a CVT) for the WRX STI S210. Still, engineers said they re-tuned it to match the power boost for a “high degree of controllability.” They’ve also incorporated a CVT fluid cooler in case owners decide to push their two-pedal sports sedans on the race track.

Engineers also worked to improve the WRX’s handling during its WRX STI S210 transition. It comes with a flexible front tower bar and additional stiffeners front and back. Likewise, the ZF adaptive dampers (standard in the WRX tS) have been retuned, while the rear stabilizer bushings have been revised. The brakes have been uprated to 18-inch front ventilated cross-drilled Brembos (17-inch cross-drilled ones at the back), while the electric brake booster’s been recalibrated. Finally, there are larger 19-inch forged BBS alloy wheels at each corner. These are wrapped in 255/35 Michelin Pilot Sport 4S tires.

The WRX STI S210 sits 20 mm wider compared to the standard WRX and this necessitated new arch cladding (they’re still black though, but now finished in a high-gloss finish). This is completed by an STI front splitter, rear diffuser, side skirts, and a weird-looking carbon fiber rear wing. Completing the exterior changes are more gloss black elements found in the grille, mirror raps, and roof antenna, while some feature the signature cherry red accents.

Inside, there are Recaro front bucket seats with carbon fiber backrests, Nappa leather-trimmed padding, and eight-way power adjustment. The center console is now finished in a dark metallic color, while the door armrests and center console are now finished in suede (Brannove). Completing the changes are red seat belts and S210 badging.