Subaru has delivered a price shock with its hardcore new Impreza 2.5 WRX STI Type UK – unveiled at the Bologna Motor Show (November 5 – 16).

The much-anticipated range-topper will cost £24,995 on-the-road – £1,600 less than the old model and much lower than expected.

Developed by a dedicated team of performance-loving engineers, the stunning new WRX STI’s first UK appearance will be at the Autosport International Show at Birmingham’s NEC (January 10-12, 2008). First deliveries are expected next March.

And with a heavily-revised new 300 PS turbocharged 2.5 litre ‘boxer’ engine, totally new platform and suspension plus even more advanced symmetrical all-wheel drive system, the World Rally Championship look-alike is sure to satisfy Subaru traditionalists.

Its proportions are radically altered compared to both the previous Impreza and mainstream new 1.5 and 2.0 litre models. For example, the wheelbase is 95 mm longer than the old car despite overall length being 50 mm shorter. This reduces front and rear overhangs and enhances stability. And at 1,795 mm wide, the new STI is even 55 mm wider than the new model thanks to heavily blistered wheelarches, while front and rear tracks are 45 and 40 mm greater for a ground-hugging stance.

Apart from the extended front and rear wings, key visual differences include a mesh front grille and a new, deep bumper design with sporty vertical air vents at either side to help cool the intercooler. Immediately behind each front wheel is a vertical air outlet for the intercooler, topped by an ‘STI’ moulding plate.

Specially-designed side skirts neatly blend into the extended wheelarches, while an oversized roof spoiler with high-mounted stop lamp further distances the WRX STI from the mainstream Impreza. In addition, an integrated rear bumper diffuser reduces high-speed lift.

At the rear, four exhaust pipes twinned in pairs at either side of the body not only give a distinctive look but reduce exhaust air-flow resistance by 38 per cent, increasing power and reducing noise.

Colour choices will include Subaru’s signature ‘WR Blue’ and while gold-coloured alloy wheels are available, other designs include high-lustre silver alloys measuring 18 x 8.5ins with 245/40R tyres.

The new Impreza WRX STI’s standard equipment is extremely generous and includes: Multi-mode Driver Control Centre Differential, Subaru Vehicle Dynamics Control system, ABS with EBD, Brembo brakes, cruise control, front, side and curtain airbags, 17 x 8 ins alloy wheels with 235/45 tyres, HID headlamps, Alcantara and leather front bucket seats, climate-control air-conditioning, 6-disc in-dash CD autochanger and MPS input.

The new Impreza WRX STI boasts a much plusher interior than before, offering leather/Alcantara-covered sports seats as standard with Recaro seats as an option. Curtain airbags are standard and the audio system has been upgraded.

Continuing on the comfort theme, the totally new suspension combines outstanding road-holding and driver involvement with a much smoother ride for passengers thanks to the multi-link double-wishbone rear suspension.

Like the previous Impreza WRX STI, the new car has inverted front suspension struts which provide a more rigid mounting and less camber-change during hard cornering. Aluminium front suspension lower arms reduce unsprung weight.

And for an even lower centre-of-gravity for enhanced grip, the front of the engine is 22 mm lower than before with the differential centre down by 10 mm.

The braking system has been developed in conjunction with Italian specialist, Brembo, and features four-pot callipers at the front and twin-pot at the rear – both ventilated discs. The system also includes four-channel, four-sensor Anti-Lock with Electronic Brakeforce Distribution.

A multi-mode Vehicle Dynamics Control System allows the driver to select the best setting for the prevalent road conditions. For example, it can be turned off altogether or set to ‘Traction’ which delays artificial interference.

The award-winning 2.5 litre horizontally-opposed ‘boxer’ engine benefits from a thorough revision which includes a larger and more efficient intercooler which increases power.

All European Impreza WRX STI models will feature the 2.5 litre ‘boxer’ engine unlike the Japanese domestic version which has a higher-revving 2.0 litre turbo.

The new STI also boasts stronger low to mid-speed torque thanks to variable-valve timing for the intake and exhaust system and a fast-warm catalytic converter for reduced emissions.

Power is now 300 PS at 6,000 rpm with torque of 300 lb ft at 4,000 rpm – increases of 19 PS and 11 lb ft respectively.

Top speed is 155.3 mph with a 0-60 mph time of only 4.8 seconds. Fuel consumption is improved compared to the old model at 20.5/34.4 and 27.4 on the Urban/Extra Urban and Combined Cycles.

Also new is Subaru’s Si-Drive system as fitted to the Legacy 3.0R spec.B. This gives the driver three different engine-response programmes at the turn of a switch, ‘Super-Sharp’ Mode giving the ultimate in throttle response.

The much-praised six-speed manual transmission has been revised, with a shorter-throw gear-change and lighter movements, especially from neutral to 1st and 1st to 2nd gear thanks to a revised synchromesh.

As before, the symmetrical all-wheel drive system features a centre viscous-coupling plus front and rear limited-slip-differentials. This shares grip front to rear and side-to-side, constantly adjusting for maximum road-holding.

A firm favourite with existing STI owners, the Driver’s Control Centre Differential has been improved, giving even more choice of handling characteristics.

The DCCD is operated via a switch in the centre console, allowing the driver to manually select the torque distribution front to rear, reverting to automatic mode every time the ignition is switched off. For example, he or she can choose between having a sharper cornering turn-in or more stable straight-line running.

In Manual Mode, the driver can adjust the front to rear torque distribution through varying degrees to suit different road conditions such as loose gravel or soft snow.

Now, for the new Impreza WRX STI, the DCCD switch also allows the selection of three different types of ‘Auto’ Mode.

1: Auto Mode is selected when the engine is started and covers most road conditions.

2: Auto+ Mode places the emphasis on traction for slippery roads, sharing out the torque more evenly between all four wheels and enhancing straight-line stability.

3: Auto- Mode increases agility by enhancing steering response through less torque-split interference.

All Imprezas marketed by Subaru (UK) Limited come with the reassurance of a three year or 60,000 mile warranty plus 12 year anti-corrosion cover and three year paintwork warranty.

This is in addition to three years’ membership of Subaru Assistance – a comprehensive home and roadside repair and recovery package throughout the UK and Europe.

Subaru (UK) Limited plans to introduce a higher-spec Impreza 2.5 WRX STI Type UK later in 2008 with a power boost courtesy of Prodrive of Banbury.