Subaru Tecnica International (STI) has decided on the standard specification of the FIA (International Automobile Federation) Group N car with the new Impreza WRX STI, sold by FHI as a base vehicle. They will be sold at specially agreed motorsport bases (STI base teams) in Europe, South Africa, etc. for use as rally base cars.
The new IMPREZA WRX STI (vehicle type: Subaru CBA-GRB) that went on sale on October 24th for the domestic market is a 5 door car with the combination of Subaru’s unique symmetrical AWD chassis layout and high power horizontally-opposed 2 liter turbo engine. They have continued development for the customer-prepared Group N rally cars to be presented in 2008 or after, exchanging information with the FHI production car development team, to improve elements and the competitiveness necessary for rallying. As soon as the base vehicles go on sale, the FIA VO parts for Group N and the STI sport parts for increased competitiveness will be released. FHI has decided that they will apply for FIA Group N status for the new IMPREZA WRX STI, and are aiming to get approval on January 1st 2008.
The new IMPREZA WRX STI features improved basic chassis functionality, including increased maneuverability through modifications to the front suspension geometry, better stability in straight line movement through a larger wheelbase, and better road-holding through the adoption of a double wishbone rear suspension. In addition, by adopting an active valve control system (AVCS) that sucks in emissions, an electronically controlled throttle, strengthened conrods and such, they have increased engine performance ? mainly the power output and torque, allowing for even more precise engine settings. The 3-mode SI drive and multi-mode DCCD (drivers control differential) - which control the different characteristics of the engine fs torque - have computerized controls, allowing users infinite possibilities in rally competition. In addition to all this, they have cut back on the rear overhang, altered the distribution of weight in the front and rear, raised the centre of gravity, and optimized the height of the roll centre, all of which contribute to the increased performance in rallying of the new machine.
STI has been working on the development of the new IMPREZA WRX STI Group N model for a long time, cooperating with the previously mentioned STI base teams, finalizing the standard specification after development tests carried out in Europe and South America. The results of rough gravel tests in South America and the twisty smooth gravel tests in Northern Europe have shown that the new model has better performance through improved times recorded on these tests.
The Group N base vehicle, based on the domestic Japanese model, will be delivered to STI base teams around the world for the 2008 season.