Subaru hopes the new Impreza will compete more directly in the European market with rivals such as the Honda Civic, VW Golf and Mazda 3. While that might be good news for sales volume and for Subaru's bottom line, it isn't exactly a cause for celebration if performance is at the head of your list of priorities. The new Impreza's hatchback body, and the early focus of the range on the low-spec models, are further worries.

But it's not all bad news. Look at the engineering built into the new Impreza and you'll find hints that the top STI turbo models could be very special indeed. And though the full-house STI won't be with us until early next year, there will at least be a 230bhp WRX turbo – available in limited numbers only – to add a dash of pace to the range. 

According to Subaru’s overseas sales chief, Mat Negato, the new Impreza was a hit in Japan, where it went on sale in June. the summer, 3829 cars were sold in the first week alone. ‘We sold 4000 units in the first week, and 6000 in the first three weeks,’ he said. Whether the new car proves to be as popular when it comes to the UK this autumn – and whether the STI lives up to the high standards of its forebears – remains to be seen.

Bigger, but is it better? 

Opinions vary on the new car’s styling, but certainly it’s had less than unanimous praise. There are criticisms that it’s bland and lacking character. Whatever the aesthetic merits or otherwise of the shape, the new five-door body does give the 2008 Impreza more interior space than before. It’s shorter and wider, and it’s that extra 2in (45mm) of interior width which is particularly noticeable.

Inside there’s a greater concentration on safety equipment than before – so in all new Imprezas you’ll find driver, passenger, curtain and side airbags. The front seatbelts have pre-tensioners, the front seats have energy-absorbing backs and most models have anti-whiplash head restraints. In the rear seat are two ISOFIX-compatible child seat mountings.

The new body is lighter than the old thanks to such measures as the elimination of the front sub-frame. A new box-section for the front cross-member provides the same level of rigidity, the structure is better at handling impact forces, and there’s a net gain of about 20kg in overall weight.

In fact, the new Impreza WRX five-door is a full 30kg lighter than the previous Sports Wagon – which means it weighs in a kilo or two lighter than the current four-door Impreza saloon. Subaru also make much of the new models’ lower drag coefficients (0.35 for the new WRX, 0.37 for the outgoing model) but diplomatically avoid mentioning frontal area. That has probably increased slightly due to the new car’s greater width, so aerodynamic efficiency is unlikely to have changed a great deal.

Engines

The existing flat-four engines are carried across to the new Impreza, with mild revisions. As before all the engines have electronic throttles, twin overhead camshafts on each cylinder bank and Subaru’s Active Valve Control System (ACVS) variable valve timing. The 2.0-litre normally aspirated engine has revised combustion chambers and cooling, a new intake system and new catalytic convertors. It loses a little top-end power but gains low-speed torque.

The 2.5-litre turbo WRX engine has been revamped to improve efficiency and throttle response. Maximum power and torque are 230ps and 236lb ft, identical to the outgoing WRX, but both peaks now occur at lower engine speeds: maximum power arrives at 5200rpm (instead of 5600rpm) and maximum torque is delivered at 2800rpm (instead of 3600rpm). Torque at low engine speeds is claimed to be considerably better than before, which should translate into much livelier acceleration from low engine speeds. The improvements come from a new turbocharger and intercooler together with a revised oil pump, spark plugs and intake system.

Transmissions

All new Imprezas receive slicker-shifting five-speed gearboxes, with a double-cone synchroniser for second gear giving a lighter change. The old cable clutch operation is replaced by hydraulics. The four-speed automatic – a £1000 option – incorporates a lock-up clutch to improve efficiency when cruising.

As with previous models, the full-time all-wheel drive transmission features a 50/50 front to rear torque split on manual models and 60/40 on the automatic. However, the split varies according to changing conditions.

The manual Impreza has a centre differential with viscous coupling which senses which axle has the better grip and distributes torque accordingly to minimise the risk of wheelspin. On automatic models, a similar function is carried out by Subaru’s Active Torque Split system using a multi-plate clutch.

The new WRX incorporates a mechanical limited-slip differential at the back in place of the viscous unit on the outgoing car. Subaru say this reduces weight and improves fuel consumption.

All but the 1.5 models feature Subaru Vehicle Dynamics Control. Sensors detect sudden steering inputs and the onset of understeer or oversteer, then brake each wheel independently to correct the car’s attitude. The system has previously only been available on certain automatic versions of the Forester and Legacy/Outback.

Suspension and brakes

Grip is aided by front and rear tracks which are 2in (50mm) wider than before, and a 10mm-lower engine position which helps the centre of gravity. The new body provides a 3.7in (95mm) longer wheelbase, which should improve mid-corner stability at the expense of slower turn-in. But that might not be too noticeable thanks to the fitment of a new steering rack with a quicker ratio (15:1 compared to 16.5:1). The rack is also more rigidly mounted, and it has a variable capacity power steering pump to improve fuel economy.

At the front, there’s a new design of MacPherson strut front suspension based on that in the Legacy, which is said to offer high lateral rigidity to improve steering response and stability. At the rear there is a new multi-link suspension system, which has been adopted to improve luggage space and reduce road noise compared to the previous all-strut suspension.

Subaru claims a ëhighly-absorbent ride with precise geometry control for accurate straight-line running over uneven road surfaces backed by extremely responsive steering and handling.’

Prices and Availability

Non-turbo Imprezas will be in the showrooms late in September, starting at £12,495 for the 1.5R. The 2.0R is £14,995 and the more comprehensively-equipped 2.0RX is £17,495. Automatic transmissions are available for an extra £1000.

The WRX turbo – the range flagship, until the STI arrives next spring – will cost £19,995 on-the-road, which works out at £1,102 less than the outgoing model.

All UK Imprezas have alloy wheels, climate-control air-conditioning, radio/CD player, height and reach steering-wheel adjustment, foglamps, front and rear electric windows, a full complement of airbags and a vehicle information display.

The WRX adds 17in alloy wheels, a front air dam and rear spoiler, side skirts, a rear diffuser, leather-covered steering-wheel and gear-knob, a rear limited-slip-differential with Subaru Vehicle Dynamics Control, 10-speaker, six-disc radio/CD player and xenon headlamps.

2008 Subaru Impreza 2.5WRX Specifications

ENGINE

Horizontally opposed four-cylinder, mounted longitudinally; aluminium alloy cylinder block and heads.  Four valves per cylinder, dohc per bank. Turbocharger with air-cooled intercooler, Active Valve Control System (AVCS)

Capacity (cc) 2457

Bore x stroke mm (in) 99.5 x 79.0 (3.92 x 3.11)

Compression ratio 8.4 : 1

Fuel system Multi-point injection

Max power PS 230 at 5,200rpm

Max torque lb ft 236 at 2800rpm

TRANSMISSION

Manual 5-speed synchromesh. Full-time AWD, centre differential with viscous coupling.  Dry single plate diaphragm clutch. Lightweight limited slip rear differential (mechanical). Vehicle Dynamics Control

Fifth gear 22.6mph/1000rpm

SUSPENSION

Front MacPherson struts, anti-roll bar

Rear Multi-link, coil springs, anti-roll bar

STEERING

Rack and pinion, speed sensitive variable power assistance

BRAKES

Dual circuit diagonally split hydraulic system with pressure limiting valve and vacuum servo.  Ventilated four-pot front and two-pot rear.  4-sensor, 4-channel ABS with electronic brakeforce distribution (EBD)

WHEELS

17 x 7 ins

TYRES

205/50R17

DIMENSIONS/WEIGHT

length, in (mm) 173.8 (4415)

width, in (mm) 68.5 (1740)

height, in (mm) 58.1 (1475)

Wheelbase, in (mm) 103.1 (2620)

Tracks, in (mm) front 58.8 (1495), rear 59.0 (1500)

Turning circle, ft (m) (kerb to kerb) 34.8 (10.6)

Kerb weight, lb (kg) 3075 (1395)

Gross weight, lb (kg) 4233 (1920)

Payload, lb (kg) 1157 (525)

Towing weight, lb (kg) braked 2646 (1200), unbraked 1433 ( 650)

Luggage capacity cu.ft (litres) 19/44 (538/1257) seat up/down

FUEL CONSUMPTION AND CO2

Department of Transport fuel consumption figures, mpg (litres/100 km)

Urban 19.8  (14.3)

Extra Urban 34.4  (  8.2)

Combined 27.2  (10.4)

CO2 emissions g/km 246

PERFORMANCE

Acceleration 0-60 mph, sec  6.1