The Mini All4 Racing has been developped by MINImotorsport for the X-raid Team. The car is currently participating to the Dakar Rally with Stéphane Peterhansel as pilot and having won the Dakar 2012 for its first year participation.
Mini All4 Body
The chassis of the MINI ALL4 Racing provides the basis for the modifications required for use in rallying. The MINI ALL4 Racing is about five percent larger than the series version. Carbon fiber is the dominant element in the bodywork. The uniform 50-millimeter steel pipes used in the roll cage are in line with the standards applied by the aircraft construction industry (as are all the steel parts). The roll cage is partly adhered to the bodywork. The enclosed passenger cell is the only component of the car that cannot be taken apart, while all the remaining parts on the MINI ALL4 Racing can be dismantled separately into other individual parts.
All4 Racing Aerodynamics
An optimized airflow on the MINI ALL4 Racing is just as important at the Dakar as it is in any other forms of motorsport. The ventilation on the MINI ALL4 Racing takes place via the roof. This can be seen from above in the form of three holes in the rear area of the roof. Behind these is located a rounded spoiler, which guides warm air from the rear area of the car over the roof, thus producing extra downforce. Because the MINI Countryman already has a spoiler on the trailing edge of the roof, it was not necessary to reintegrate a rear spoiler for the MINI ALL4 Racing, but simply to modify the airflow to suit the demands of the Dakar Rally.
Mini Rallycar transmission
The MINI ALL4 Racing is equipped with a Sadev six-speed, sequential gearbox with six forward gears and one reverse gear. When starting the car moving, the gears are shifted using the AP Racing clutch. Once the car is in motion, it is possible to change gear without using the clutch. Unlike with the MINI John Cooper Works WRC, where the gear lever is located directly next to the steering wheel, the gear lever is positioned between the driver and the passenger, as in a production car. The gears are not arranged in the conventional H pattern, however. The gear lever is simply moved backwards to move up a gear and forwards to move down a gear.
The clutch is a production-based sintered clutch, in order to be able to transmit the large amount of torque from the engine. The MINI ALL4 Racing is also equipped with lockable oil-cooled Xtrac front, middle and rear axle differentials.
Mini All4 Racing Engine
The diesel engine that powers the MINI ALL4 Racing was designed by BMW Motoren GmbH in Steyr, Austria, to be used in endurance races under the toughest conditions. The twin turbo engine with a capacity of 2993 cubic centimeters is based on a BMW production engine and generates over 300hp at 3250 revs per minute. This allows the MINI ALL4 Racing to hit a top speed of 178 km/h. The diameter of the air restrictor is 38 mm.
The engine is also equipped with a dry sump lubrication in order to limit the overall height and guarantee optimal lubrication under extreme conditions. The wiring was reduced to the bare minimum in order to further reduce the weight of the car.
The cockpit of the MINI ALL4 Racing provides the drivers with a lot of space. Both driver and co-driver sit in specially formed Recaro Motorsport seats and are secured by six-point harnesses. The HANS (Head and Neck Support) safety system is also used.
The dashboard in the cockpit is made of carbon fiber and consists of three parts: a driver dashboard, a center dashboard, and a co-driver dashboard. The information displayed there is reduced to the bare minimum. The driver sees a gear display and a switch symbol, indicating that he needs to change gear. Central information, such as speed, oil pressure, temperatures and electronics information are displayed centrally, thus making them visible to both the driver and co-driver. This element can be removed and replaced within three minutes, thus optimizing servicing times should it stop working for any reason. The co-driver dashboard contains the navigational elements.
Tire and brake system
The MINI ALL4 Racing is equipped with Michelin All-Terrain tires in size 245/80R 16. In addition to the four tires mounted on the vehicle, up to three spare tires are also located in the rear of the MINI ALL4Racing. The inner-vented, steel disc brakes (320 millimeters by 32 millimeters) are air-cooled on the front axle and water and air-cooled on the rear axle (six pistons each). The shock absorbers (four on each axle) can be set to four levels. An adjustable roll valve can be used to change the car’s roll. The damper oil is cooled via an external reservoir, which allows a more continuous dampening and a longer damper life cycle.
Romain Nicolas opinion:
This rally car looks pretty optimized and it seems that Mini has put a lot of development efforts on the car. How did they verify the endurance and reliability of components and systems? How long did it take to develop such a rally car?