Meet the STI S209, a rather special Subaru unveiled at the 2019 Detroit Motor Show as something of a swan song for the current-generation WRX that continues the S designation that was previously only reserved for limited run Japan-only editions. That the US market is getting one at all is something of note.
It also happens to be the most powerful WRX the Japanese automaker has ever produced, thereby making it the most powerful street Subaru ever, which is surely handy to mention at your local cars and coffee meet. Subaru says that, with the S209, more than a few choice items and design inspirations were taken from the Nurburgring Challenge racer, and it’s hard to ignore this car’s extra aggressive presence.
Only 200 examples are set to be produced, however, and so numerous are the modifications made over any typical WRX that they had to homologate the S209 under the STI brand instead of Subaru. How hardcore is that?
To improve aerodynamics and increase downforce, the car wears a bespoke exterior kit that adds bigger fenders to accommodate the 15mm wider track, front canards and a fixed carbon fibre rear wing that could not have escaped anyone’s notice. On the suspension front, it’s basically all new as well with a flexible strut tower bar and draw stiffeners augmenting competition-spec springs and Bilstein dampers.
A set of 19-inch BBS forged wheels now adorn the car’s four corners, shod in specially-developed Dunlop SP Sport Maxx GT600A tyres with a bespoke compound to complement the S209 characteristics. Taken as a whole, the S209 is now able to pull 1.0g in lateral grip on the skid pad. Stopping power is upped as well thanks to larger Brembo brake rotors and callipers.
As you’d expect, we find a flat-four EJ25 Boxer under its bonnet, but the 2.5-litre engine has been thoroughly fettled to produce roughly 250kW thanks to a new HKS turbocharger that raises boost to 18psi (1.8psi more). To handle the higher internal pressures and heat, forged pistons and connecting rods were installed.
Elsewhere, its intake system has also been revised to ensure a higher volume of cool air is always being supplied to the engine, paired with a higher flow petrol pump, larger fuel injectors, and a freer-flowing exhaust system. Not even Subaru (oops, STI) have an exact figure at the ready, insisting that the quoted 341 horsepowers being merely a close estimation. The mind boggles.
Regardless, power is routed through a close-ratio six-speed manual transmission and is distributed to all four wheels per Subaru’s Symmetrical All-Wheel Drive system with front/rear limited slip differential with Active Torque Vectoring.
There are no plans to bring the S209 to any other market other than the USA, unfortunately. Even the company’s home market across the Pacific will be left in the lurch, at least until Subaru tops themselves with perhaps another S edition WRX. Puzzlingly, only one of the two colour options, Crystal White Pearl, is offered with these gold painted wheels. The more recognisable WR Blue Mica, is fitted grey wheels.