Subaru's super-quick Cosworth STi unveiled

The Cosworth Impreza STI CS400 is capable of 3.7 second sprints to the legal limit. Photo / Supplied

Subaru has unveiled a higher-performance version of the Impreza, which owes its speed to a programme of upgrades provided by motor racing specialists Cosworth.

Perhaps the most important improvement is a 33 per cent power boost for the already powerful 2.5 litre Subaru boxer engine, which takes its total output to 249kW (400hp).

That allows the Cosworth Impreza STI CS400, as the new car is badged, to accelerate from rest to 100km/h in just 3.7 seconds, although like most other very quick models, its top speed is artificially limited to 255km/h.

The Impreza's characteristic Subaru drivetrain, which features a geometrically very "pure" all-wheel drive system, is retained, but has been uprated in order to handle the increased power of the Cosworth-modified engine.

Eibach springs and Bilstein dampers feature among the improvements to the car's suspension set-up.

Subaru will probably be hoping that this new Cosworth inspired variant will help to quell some of the grumbling from fans of the brand that the current Impreza, while rapid and capable, is a bit "soft" compared with the previous version.

On the other hand it does represent a bit of departure from Subaru's recent tendency to play down the sporty side of its range.

- THE INDEPENDENT