Mitsubishi MiEV Evolution

Mitsubishi Motor Company (MMC) formed the MiEV Evolution project in the run up to the 2012 race season. There were 2 stated aims; to promote the consumer i-MiEV electric car (which began to sell in North American markets in late 2011), and to participate in the PPIHC as a competitive event which has a long-standing tradition of experimental motor sports and is therefore a potentially suitable venue to test and improve the technologies of electric motor sports vehicles.^[2] Being a high altitude event (with the finish line around 14,000 feet), with diminishing oxygen levels in the upper stages which affects the efficiency of internal combustion engines, the Pikes Peak race venue is particularly favourable for electric power-train vehicles.

For the initial 2012 PPIHC race, the team took existing powertrain components from the iMiEV production car, using 3 of the car's standard electric motors, retuned to rev to 11,000rpm and each producing a maximum of 107 bhp and 148 lb ft of torque^[3] for a total of 322 bhp and 443 lb ft of torque. One motor powered the front wheels, and the remaining two were harnessed in parallel to drive the rear wheels. The vehicle carries 35KWH of batteries and has a total weight (with driver) of 1400 kg - considerably more than its gasoline-powered competitors. The car's acceleration creates a 0-60 mph time of 3.8 seconds,^[4] and it has sufficient handling to achieve up to 1.3 lateral G in cornering.^[5] The top speed is 115 mph.

For the 2013 season, the team prepared a new vehicle, known as the MiEV Evolution II. With more time in hand, the team was able to implement more sophisticated drive control, allowing power to be directed to each wheel independently (instant torque vectoring),^[6] improving traction and handling. Total power was increased to 536 bhp and 885 lb ft of torque.^[6][7] The onboard energy storage was increased to 50KWH, and top speed increased to at least 140 mph.^[7][8] The design also featured improved aerodynamics, reduced weight, a lower centre of gravity due to repositioning the batteries, active yaw control, active stability control and a redesigned anti-lock braking system. The vehicle rides on Dunlop 260/660-18 tyres,^[9] and overall dimensions are Length x Width x Height (mm) - 4,870 x 1,900 x 1,390.

For the 2014 season, the team produced the MiEV Evolution III. Power was further increased, to 604 bhp,^[10] and the gearing ratio changed to improve acceleration out of corners.^[11] The battery remained at 50KWH, and redesign and use of different materials further reduced chassis weight. Wind tunnel work led to further downforce and aero-dynamic improvements, and the all-wheel traction control system was improved. The vehicle rides on wider Dunlop 330/680-18 tyres, and dimensions are Length x Width x Height 5,190mm×2,000mm×1,485mm, an increase over previous years. Without providing detailed data on the overall vehicle weight, Mitsubishi has confirmed^[11] that the MiEV Evolution III is lighter than the previous generations, i.e. under 1400 kg.^[12] For comparison, the 2013 winning unlimited class vehicle (Loeb's Peugeot) was 875 kg (with 875 bhp). Official technical details about the vehicles can be found via Mitsubishi's news website.^[13]