Chassis
Few things are unchanged on the Evolution VII. Beginning from the ground up, chassis engineers made it their goal to give the new car better rigidity, as well as a longer track. The Evolution VII's overall length and wheelbase are 4.1 and 4.4 inches longer than the Evolution VI's, respectively. Even more important, the VII has longer shock travel, perhaps one of the most important aspects of a car like the Evolution. According to Mitsubishi, the design centered around building a car that could win races.
If this is the case, then a careful look at the specs of the Evolution VI and VII together raises a few questions. Not only is the new body longer and taller, it's also 88 lb. heavier in GSR trim. Extra weight rarely improves things in competition.
So how do the engineers justify the added pork? The new body was required to gain the extra length and suspension travel needed to keep the Evolution competitive in Group A and N rally competition. Building from the existing platform would have added even more weight in the way of additional chassis braces. However, by designing an all-new body structure, engineers were able to incorporate added stiffness into the design, while using extra reinforcements only at load-bearing areas.
Drivetrain
The new Lancer retains Mitsubishi's highly touted 4G63 powerplant, which has been used successfully in the Lancer series since the car's introduction in 1992.
For the Evolution VII, however, the engine has been changed significantly to improve torque and reduce weight in an effort to compensate for the additional weight found in the new body.
Intake and exhaust plumbing efficiency have been improved by straightening the exhaust and slightly modifying the intake manifold. Aluminum replaces steel in several intercooler pipes and hollow camshafts also contribute to engine weight reductions.
The VII's intercooler is .75 inches wider than that of the Evolution VI and is cooled with three water sprayers as opposed to the two of the former car. The Evolution VII's water sprayer can be set in manual or automatic modes. In automatic mode, it sprays for 2 seconds in 5-second intervals, depending on driving conditions. A larger oil cooler further enhances engine durability.
The most significant change to the new Lancer engine was executed at the turbocharger. A smaller turbine nozzle diameter (A/R) results in an improvement of 7 lb-ft of torque (282 lb-ft at 3500 rpm vs. 275 lb-ft at 3000 rpm) when compared to the Evolution VI. Horsepower is still set at the Japanese standard (276) and is produced at 6500 rpm.
Since the Evolution IV, the Lancer has been at the forefront of drivetrain technology and the Evolution VII takes that magic a step further. Replacing the viscous coupling in the Evolution VI is a hydraulically actuated clutch-type active center differential (ACD) capable of delivering up to three times the torque split to either end of the Lancer relative to the former viscous coupling.
In theory, this should allow for better control over the car when the tires begin to slip. However, controlling the differential is an ECU with user-selectable differential maps for tarmac, gravel or snow. ACD uses steering angle, throttle position, longitudinal and lateral acceleration sensors, individual wheel speed sensors and input from the ABS ECU to improve stability. This technology is no doubt a trickledown from the World Rally Championship cars, which have been using active differentials for some time.