Subaru is making a version of the WRX STI S209 exclusively for the US market.

We knew that Subaru would finally bring the S-series of WRX STI sedans to America thanks to a bevy of teasers that the Japanese carmaker released shortly before the Detroit Auto Show.

What we didn’t know was what would be under the hood. All previous versions of the best-of-the-best S-series STIs have always been restricted to the Japanese market, which meant they came with a 2.0-L turbocharged boxer-four engine. North America has always gotten a 2.5-L turbo boxer-four, which surprisingly made less power than the smaller Japanese version.

We were worried that the first ever S-series STI to come to America would still use the 2.5-L engine but be less powerful than its Japanese counterpart. Well, our worries are all for nothing as Subaru has announced that the EJ25 2.5-L turbocharged 4-cylinder engine now makes 342 hp in the America-spec S209.

That’s up from the Japanese-only S208’s 329 hp, but is still less than the most powerful STI ever made, the South African Diamond Edition, which makes 349 hp.

Besides the up-tuned engine, the S209 also sports similar upgrades to last year’s S208, but with subtle differences to make it clear this is the US-spec model. The front fascia remains mostly the same as before, but now the S209 has wider fender flares and small black vents just behind the front wheels.

RELATED: SUBARU STI 'S209' WILL BE AT DETROIT AUTO SHOW

Check Out Subaru's WRX STI S209 With Wider Body & More Horsepower
via Subaru

As with previous years, the S209 gets a carbon fiber roof and rear wing, as well as 19-inch BBS wheels wrapped in Dunlop SP Sport Maxx GT600A tires. Brembo 6-piston calipers are in the front along with 4-pistons in the rear, and Bilstein dampers carry over for the suspension. In addition, the S209 has a new flexible front-strut tower bar that laterally strengthens the chassis and allows for a sustained 1 G turn.

On the inside, the S209 gets an Ultrasuede-covered steering wheel and Recaro bucket seats.

Only 200 units will be made exclusively for the US market. Pricing and availability have yet to be announced, so stay tuned to own the very best STI Subaru has ever made.

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