Finally Official: The Cosworth Subaru Impreza STI CS400!

I'll readily admit, I've been waiting for this car to surface fully with baited breath for months. I mean, it combines two of my absolute favorite things in the automotive universe:  flat-four Subarus, and British tuning firm Cosworth, who can turn even a complete turd of a motor into something respectable.  If you need proof of this, remember:  The Cosworth 2.0L in the Sierra/Escort Cossie was based on a Pinto block, and the Cossie boys also made a screaming 16v all-aluminum version of Chevrolet's lamer-than-lame Vega motor.

Now, perhaps the Cossie fellas are being a  bit ostentatious with their claims that this latest creation, the Impreza-based STI CS400, will humble supercars.  But when your Impreza hatchback is capable of a 3.7 second 0-100km/h time, maybe there's something to be said for the substance of your claims.  That's up there with Lamborghini Gallardos and 911 Turbos in the "going fast" category.  So how does one extract this much performance from a tiny 2.5L pancake-four motor?

Boost, and lots of it.  The twin-cam EJ257 is treated to new pistons, connecting rods, Cosworth bearings, a high-pressure oil pump, a set of heavy-duty metal headgaskets, a larger turbocharger, a free-flow exhaust system, and a remapped ECU - typical Subie mods.  Total power output is a stunning 395bhp along with 398 lb-ft of torque - or about 33% more on both ends than the already powerful stock STI engine is cranking out.  Thankfully, Cosworth doesn't stop there.  An adjustable suspension with Bilstein dampers and Eibach springs drop the Impreza's chassis 10mm, 18" wheels mount sticky DOT-legal race slicks that widen the track by 12mm, while larger 355mm AP Racing brakes up front keep things in check.

Thankfully Cosworth hasn't seen fit to stick a bunch of goofy body parts on the Impreza, with just a handful of tasteful mods setting the CS400 apart from it's more mainstream brethren.  A new front bumper, foglights, a body-colored grille, and a small rear lip spoiler set the car off, along with some "Cosworth" and "CS400" badging to remind you why you paid that much for an Impreza.  There's not much changed inside, with piano-black lacquer trim, Recaro seats, Cosworth badging and tinted glass rounding out the changes.

With a 0-100km/h time of 3.7 seconds and an electronically-limited top speed of 155mph, the Cosworth-engineered CS400 is fully capable of running with the big boys.  And with a price tag of £49,995 it's priced like the big boys too.  The question of "is it really worth almost $75,000 for a Subaru Impreza?" is most likely an irrelevant one, as Cosworth is only producing 75 examples of the re-engineered CS400 in right-hand-drive for the UK market.  Regardless, if you get your hands on one, you'll have the fastest road-going Subaru ever, not to mention "Cosworth" badges that are worth their weight in gold, so that's got to be worth something, right?