2006 Subaru Impreza WRX STi WRC

Based on the new Subaru Impreza, introduced in 2005, the Subaru Impreza WRC 2006 prototype harnesses the knowledge of over 15 years of continuous participation in the FIA World Rally Championship (WRC). The bold new aerodynamic design and systems incorporated in the vehicle have all been designed with the goal of improving its competitiveness in WRC events.

A History

The story behind the Impreza's success is best told by the raw statistics: six World Rally Championship titles and 46 outright rally wins. The Impreza has been the defining car in Subaru's elevation from relative obscurity to a legend in world rallying. From its inception in 1993, the Impreza has provided a sensory assault on motorsport fans across the globe. Subaru's blue and yellow livery is now as iconic as the flat-four engine note which trumpets the car's continued success. And for a great car, there have been great drivers: Ari Vatanen, Kenneth Eriksson, Colin McRae, Carlos Sainz, Juha Kankkunen, Tommi Mäkinen and the sadly-missed Richard Burns have all succeeded with the car down the years. Most recently, Petter Solberg has made the Impreza his own, demonstrating its undiminished appetite for glory when he won the 2003 Drivers' World Rally Championship title.Success and planning for the future
Subaru signalled an increased commitment to rallying in 1989 when it joined forces with motorsport preparation specialists Prodrive to campaign the new Legacy RS. The Subaru World Rally Team was born out of the alliance and domestic success in both individual rallies and championships soon followed. From the outset the team built its reputation on constant development and a willingness to experiment with cutting-edge technology – perpetual traits through the passing seasons. Within a year of joining Subaru, Prodrive was invited to contribute ideas which would make the forthcoming Impreza suitable for the stage well before the production car design was finalised.





The Subaru Impreza 555 first turned a wheel on May 19, 1993, three months before it was due to make its competitive debut. It was an improvement over the Legacy in almost every aspect. The engine offered better acceleration, more response and ran at a cooler temperature. The Impreza's enhanced handling raised cornering speeds, while the braking system was also superior.

Much of the Impreza's early success was derived from its basic layout and deliberate weight distribution. The all-aluminium engine meant less of the load hung over the front wheels, enhancing the car's balance and allowing the drivers to make a more efficient use of their tyres than any of the competition. Technological boundaries were still being pushed, however, as the car featured an active centre differential from the outset.



Winners everywhere
The team didn't have to wait long for the Impreza 555's first win. It came in Corsica, 1994, with Carlos Sainz at the wheel. The Spaniard's success marked the beginning of a triumphant period for Subaru. New Zealander ‘Possum' Bourne won the FIA Asia-Pacific Rally Championship (a result repeated by Kenneth Eriksson in 1996), while Sainz and team-mate Colin McRae claimed three further victories on WRC events.

The 1994 season had raised expectation in the Subaru camp to fever pitch. The following year delivered the dream results. McRae and the Impreza 555 swept the board, winning both the Manufacturers' and Drivers' World Rally Championship titles. The Scotsman was the youngest-ever world champion (with Sainz taking second place) and Subaru took a clean sweep of the podium positions on both the slippery mud of the RAC Rally and the dry asphalt of Catalunya; ample demonstration of the Impreza's all-round ability.

The success story continued in 1996, when another dominant season from the Impreza and team drivers Kenneth Eriksson and Colin McRae was rewarded by a second consecutive manufacturers' title for Subaru.

Enter the World Rally Car
From 1997 there was a new look to the cars competing in the World Rally Championship. A new breed of machine was created to embryonic World Rally Car specifications. Revised regulations permitted major changes, chiefly to the width of the car and suspension geometry; engine internals and the aerodynamics.

Although based heavily on the basic concept of the Group A Impreza 555, the car's successor: the Impreza WRC97 set the visual standard by which other manufacturers were judged. While engineers capitalised on the freedoms allowed by the new technical regulations, renowned auto-stylist Peter Stevens was drafted in to get the most from the aerodynamic opportunities. It was the first WRC car to be unveiled and widely acclaimed as the most visually stunning.

Immediate success
The Impreza WRC97 made the best possible debut with a win on the 1997 season opener when Piero Liatti won the Monte Carlo Rally. Seven more wins ensured Subaru was unchallenged for its third consecutive world manufacturers' title. The development of the car continued through the late 1990s, with the WRC98 and WRC99 further refining the Impreza package and incorporating the latest technological advances.

Electronic technology
Among the array of technology in the Subaru Impreza range was the unique semi-automatic gearbox, together with a fly-by-wire throttle, as fitted to the 1999 Impreza WRC. Physical selection of the gears was made by a series of hydraulic actuators, controlled by a computer. Únlike previous versions of the Subaru system, there was no gear lever in the car. Now the driver pushed or pulled a paddle to the right of the steering wheel to make selections. All modern rally cars now have this technology, but Subaru is proud to have been the first.

Bust and boom
After a comparatively disappointing 1998 season, by the team's exacting standards, and a difficult first half of 1999 where the team's efforts were dogged by mechanical troubles, a dramatic victory in Argentina in 1999 signaled a return to form. In the second half of the season the Impreza, now driven by Richard Burns and Juha Kankkunen, was once again the car to beat. Following the win in Argentina, the Impreza claimed victories in Greece, Finland, Australia and Britain. Burns ended the season as runner-up in the championship.

The WRC99 was retained for the start of the 2000 season and proved competitive with a memorable victory on its last event: the tremendously tough Safari Rally in Kenya. For the next rally of the season, the Rally of Portugal, the Subaru World Rally Team unveiled the Impreza WRC2000.

A new beginning
The outgoing Subaru Impreza WRC99 was the result of a 10-year evolution process that began with the Legacy. The WRC2000 was a complete redesign of the rally car following a 10-month development project, starting with a clean sheet of paper. Every component was examined for possible improvement and, although the end product looked similar in external appearance to the WRC99, beneath that familiar skin it was 80 per cent new.

The WRC2000 made its debut in Portugal, and, with Richard Burns behind the wheel, claimed victory out of the box. More successes followed for the WRC2000, this time in the mud and rocks of Argentina. Despite another home win on Rally GB and his most successful season to date, Burns again had to settle for the runner-up spot in the World Rally Championship.

Two-door to four-door
The one area of the Impreza WRC2000 that was not obviously different to the previous incarnations of the model was the two-door bodyshell. The same, however, could not be said of the WRC2001. More so than any other Impreza at the time, the WRC2001 was developed in tandem with its road-going counterpart, allowing Subaru's legion of fans to genuinely benefit from the technology bristling beneath the car's skin and four doors.

Design challenges
Development of the new car was in two phases. The first was the mechanical development, which had been thoroughly tested in the WRC2000, before being transferred to the new WRC2001 bodyshell. The second phase was to address the physical considerations of aerodynamics, shell strength, packaging and weight distribution. Once again, Prodrive's director of styling, Peter Stevens, was pressed in to service to oversee the external elements of the car – a project that began as early as September 1999.

Yet another world title and a new driver line up
A difficult start to the 2001 season was quickly overturned by Subaru's dedicated team of engineers. Thanks to a determined approach by Burns, the Impreza tasted the ultimate success, with a world title, on Rally GB. Victory in New Zealand earlier in the year had thrown Burns into the heart of a title battle that would go down to the wire. A controlled third place in Wales was enough to secure Burns' first Drivers' Championship and a fifth title for Subaru.

The 2002 season delivered fresh challenges. Four-time world champion Tommi Mäkinen led the Subaru World Rally Team line up, partnered by Norway's rising star Petter Solberg. Between them they ensured the Subaru Impreza success story continued. The year was bookended by victories for Tommi (in Monte Carlo) and Petter (on Rally GB). Those maximum scores, combined with a string of podium places, carried the young Solberg to second position in the title race.

Champions again!
The WRC2003 was the result of an integrated design process which brought Prodrive and Subaru closer together than ever. The two companies worked hand-in-hand to complete revisions to the engine, roll-cage, body panels and the car's overall aerodynamic package. During the 2003 WRC campaign, the car proved a significant improvement over its predecessor and powered Petter Solberg to four sensational wins and the drivers' title.

High five in the 2004
After a 14-month design and development project the next evolution of the Subaru Impreza World Rally Car, the WRC2004, made its competitive debut on the Corona Rally Mexico. Taking full advantage of the latest FIA technical regulations, and incorporating a host of improvements to areas like the bodyshell, engine, suspension, electronics systems and aerodynamics, the WRC2004 was a result of Subaru's desire to harness the engineering skills of its teams at Subaru Tecnica International (STI) and Fuji Heavy Industries Ltd (FHI) in Japan and at the Subaru World Rally Team's base in the ÚK. It did not disappoint and achieved five wins in one season. The WRC2004 was retained for the start of the 2005 season and won on its final ever official outing, when Solberg won the Swedish Rally.

All change from Mexico
Featuring a wider track, revised styling, composite body panels and a host of engine enhancements, the 2005-specification Impreza world rally car made its competitive debut on Rally Mexico. A product of the continued close collaboration between engineering and design teams in the ÚK and Japan, the WRC2005 ensured that the Impreza kept its position as a top-level contender in the World Rally Championship – despite incredibly stiff opposition.

New season, new rules
The 2006 season saw the biggest shake-up in the technical rules since the world rally car formula was introduced in 1997. In order to cut costs, active differentials and water injection were banned. Teams were also obliged to re-use cars and engines on selected ‘pairs' of events – a system which was first tried on some rallies in 2005. All these rule changes meant that Subaru, along with every other team, was obliged to run its 2006 car from the first rally of the year, rather than introducing it once the season had started. For 2007 the team will revert to the tradition of introducing its new car only when it is satisfied that the car has been fully developed into a winning proposition, so an interim Impreza will be used on the opening rallies of the year.

Source - Subaru