From £31,550
Fast, fluent and thoroughly impressive: the best fast Impreza for a decade

What is it?

The fastest, most powerful and most expensive Subaru Impreza that’s ever been offered for sale in the UK: this is the Cosworth Impreza STi CS400.

You’ll have worked out by now that, unlike pretty much every special Impreza that Britain has ever seen, this car has been developed not by Prodrive but by a different, little-known British engineering firm just up the A43, which also has quite an impressive history in motorsport (cough, cough).

See the first drive pics of the Cosworth Impreza STi CS400

Joking apart, this car is actually the first performance special that Cosworth has developed ‘solo’ since the whale-tail 1996 Ford Escort RS that bore the company’s name. The Northampton firm’s bread and butter remains the development and manufacture of high-performance engines for racing, low-volume road cars, defence and the aero industry, but for this project it plunged in with both feet and took responsibility for chassis specification and set-up, drivetrain upgrades and overall development, too.

What it has produced is a Subaru Impreza STi with a significantly upgraded engine and chassis and some pleasingly stealthy styling modifications, which is capable of cracking 62mph in just 3.7sec, and a standing quarter mile in only 12.75sec. As you’ll already know if you’ve been reading our blogs section, the latter figure is less than half a second slower than a 572bhp Audi RS6.

What’s it like?

Almost as good as you’d expect it to be, even looking back with the rosiest of specs at Cosworth’s old fast Fords. The outfit has done a very thorough job of transforming this Impreza into a rapid but useable road car, and has corrected many of the standard Impreza STi’s shortcomings in the process.

We’ll deal with the chassis and running gear first, because that’s the biggest surprise. Cosworth engineers have kept the Impreza’s major chassis mechanicals – struts up front, independent multi-linked arms at the rear – but has specced Eibach springs that allow the car to run 15mm lower on its front axle. They’ve also gone for specially tuned Bilstein dampers all round, and have changed the STi’s chassis bushings, too. They’ve chosen lightweight 18in wheels and Michelin Pilot Sport 3 tyres, as well as 355mm ventilated front brakes and six-piston calipers from stopper specialist AP.


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And as a result of all that, the CS400 is an STi that is much more controlled, responsive and precise to drive, and yet it’s also suited to rutted UK tarmac. That drop in ride height has eliminated a lot of the unsettling initial body roll that standard STis suffer with; it’s also made the car’s steering a great deal more accurate and positive, although it’s still quite light.

But it’s this STi’s damping finesse that’s most remarkable. If you’re expecting a trolley-jack ride, you’ll be blown away. The car feels like it’s got suspension travel and damper control to spare 90 per cent of the time, even on really testing backroads, and those new bushings make it surprisingly quiet and smooth over sharper intrusions.

Oddly, the Cosworth Impreza doesn’t quite blow you away where you expect it to: in the engine department. That’s not for want of effort on Cosworth’s part. It has completely stripped Subaru’s aluminium 2.5-litre flat four in the process of making this engine, and fitted new pistons, bearings, con rods, gaskets, head studs, and a completely upgraded turbocharger, intake system and exhaust. Such is the company's devotion to this car’s powerplant, Cosworth has even taken the oil pump to bits to ensure that it’s working efficiently.

There are just two problems spoiling this car’s engine. One of them is turbo lag: the CS400 has what might charitably be described as ‘soft’ throttle response. Floor the accelerator, even up at 2500rpm, and it’s usually between three and four seconds before you get full boost. Blame the Impreza’s intercooler, and its necessarily long intake plenums, for that.

The second problem, predictably, is that even on full boost, you rarely feel like you’re getting the engine’s full 395bhp. Which is because you’re not, of course; 395bhp at the crank probably translates into about 340bhp at the wheels of this car – and that’s by Cosworth’s own estimation - thanks to the efficiency losses of the car’s diff-happy drivetrain. The CS400 feels fast, but no more potent than a few other wicked-strength hatches we could mention.

Should I buy one?

You may not be able to unless you’re quick. Subaru UK is offering only 75 of these cars, and they’re almost all gone. And missing out on one would be a tragedy for Impreza devotees: this is one great fast Scooby, imperfect powertrain and all.

In the cold light of day, the Impreza CS400 is a tough car to recommend to a less partisan customer. As quick as it is, a Nissan GT-R would be faster still and is within sight on price, and either a Porsche Cayman S or Lotus Evora would make a more involving drive.

Which is why it’s such a shame that Subaru UK isn’t offering twice the number of Cosworth Imprezas at half of this car’s premium - because if this were a £40k car, we’d be recommending it to all-comers.

As it is, you’ll need to be a fully paid-up member of the fast 4x4 fan club to justify a CS400. The car, we like; the price is the disappointment.

Cosworth Impreza STi CS400

Price: £49,995; Top speed: 155mph (limited); 0-62mph: 3.7sec; Economy: na; CO2: na; Engine: 4 cyls horizontally opposed, 2457cc, turbocharged, petrol; Power: 395bhp at 5750rpm; Torque: 400lb ft at 3950rpm; Gearbox: 6-spd man

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8 September 2010

So the Scooby is still alive and kicking inside its new bodywork: handling fettled but still waiting for the drivetrain genie. Fantastic news - let's hope that this is the first of a raft of modifications and special editions that get closer and closer to releasing the full potential

8 September 2010

You'd have thought with the comprehensive overhaul of the Impreza that Cosworth have undertaken it would have made the engine a real jewel instead of this, apparently, soft, laggy pudding.

Headline performance figures aside, for £50k, you'd expect better from Cosworth.

8 September 2010

I could be wrong but the way i read the article is that it's a cracking engine it just suffers a little bit from being relatively small and so heavily reworked - I know 3-4 seconds is mentioned but i'd bet in practice that translates to a slight delay (0.5s max) followed by a build up of raw power then a sledgehammer in the back as it comes on song fully, a bit more old school if you like.

8 September 2010

Does the Scooby now sound as aggressive as it looks? I test drove two "normal" Scoobies and was dissapointed with the general silence of the car.


Bought a Golf R instead...

8 September 2010

I still looks like a Rover 200 that its chavvy owner treated to a trolley dash around Halfords ....

8 September 2010

Nice as it is, it's £ 50k.....

8 September 2010

£50,000 for a scooby, no way, i could buy a nearly new BMW M3 for the same money, sorry for me it doesn't compute.

8 September 2010

3.7 secs to 60mph? haha if only you drop it off a cliff could much that!

8 September 2010

[quote Autocar]

The outfit has done a very thorough job of transforming this Impreza into a rapid but useable road car, and has corrected many of the standard Impreza STi’s shortcomings in the process.[/quote] Forgot to correct the most important part, its still bloody ugly, to take a look at what can be achieved step forward the Prodrive P2, Prodrive said the P2 could be produced for £40k, this is what Cosworth should be doing if it wants to be taken seriously with road cars again


8 September 2010

What Subaru need to do is improve the standard car so that 75,000 people want to buy it rather offer than this niche product that only 75 people can buy. And what a tiny niche - people prepared to pay £50k for a hot hatch!


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