Speaking of Mitsubishi’s four-wheel drive technology, in addition to the famous super-selected four-wheel drive on Pajero and other models, the S-AWC used on EVO, Outlander and other models is the most powerful four-wheel drive on the surface. With it, the driving stability of the vehicle can be greatly improved performance, and driving pleasure and safety under various road conditions. S-AWC accompanied Mitsubishi EVO to compete in WRC for many years and made countless brilliant achievements. There is even a famous saying in the car industry: buying EVO is entirely for the four-wheel drive system. It can be seen how profound the skill of Mitsubishi S-AWC is! And Mitsubishi has always been a very low-key car company. Many people don’t even think it is a technological pioneer, but Mitsubishi’s black technology has been quietly launched, such as the throttleless engine technology, which relies purely on delicate intake valve control to replace the traditional throttle. function, which requires a pinnacle of knowledge in variable valve technology to be realized.
AYC, ACD, ASC, and ABS together constitute Mitsubishi’s S-AWC (Super All Wheel Control) super all-wheel control system, of which AYC and ACD are the core components of S-AWC.
ACD active differential
ACD (Active Center Differential) active central differential first appeared in Evolution VII. The role of ACD is mainly to control the power output of the front and rear wheels through a limited slip differential. The active center differential can control differential slip in good time. When driving in a straight line, the ACD is in a loose state; when cornering, the ACD will be electronically controlled according to the vehicle speed, steering angle, and steering speed to ensure the best traction and steering response; when it is necessary to lock the front and rear axles, two of the ACD The bevel gears are rigidly connected, so that the front and rear axles no longer have a speed difference, and the power of the front and rear axles is distributed at 50:50 to achieve the strongest grip.
AYC active yaw control system
AYC (Active Yaw Control system) active yaw control system, this system first appeared on the fourth generation EVO. Today’s EVO is equipped with Super AYC. Super AYC can make the two rear wheels output torque according to the actual needs, which meets the needs of the body for deflection control. The highest capability of this technology is to provide the required different torques to all 4 wheels. For example, when EVO oversteers, AYC will give a little more torque to the inner wheel to reduce oversteer; similarly, AYV will provide more torque to the outer wheel when understeer.
Distribution torque map when AYC is active
The other two equipments of S-AWC – ASC and ABS are not introduced, ASC=ESP. Talk about the overall working principle of S-AWC.
S-AWC system diagram
The combined force of the central differential and the rear axle differential is provided by an adjustable hydraulic pump. The maximum combined force is the ratio of 50:50 between the front and rear axles, and the rear axle differential can be adjusted steplessly from 0-100%. Tune. The power transmission route is: engine, transmission, front axle differential, ACD central differential, rear axle differential, and each wheel. Steering angular velocity, throttle opening, wheel speed, longitudinal acceleration and lateral acceleration are reflected to the driving computer through sensors, and the computer makes adjustments based on the situation.
Seeing this, you may feel that the components and functions of S-AWC are not very fresh. But the existence of the strongest four-wheel drive must be combined with the cooperation of other parts. As the king of WRC, Mitsubishi’s designers have their own views on designing a suitable four-wheel drive system. First, the high-torque engine. Mitsubishi engines have never dropped below 315 Nm of torque since the Evolution I. In a rally race, the size of the horsepower does not guarantee victory, but the high torque can ensure that the phenomenon of skidding is reduced on bad roads; secondly, the battery of Evolution is arranged in the luggage compartment, and the front and rear axles are balanced. Finally, Evolution has never stopped moving towards the goal of lightweight. The suspension and frame are made of aluminum alloy, and it is the first to use aluminum-titanium alloy for turbine blades. The combination of these three points truly constitutes the title of Mitsubishi Evolution’s strongest four-wheel drive on the surface.
In fact, the reason why S-AWC can cooperate so well with Evolution is partly due to the efforts of engineers, and partly due to the WRC. It is under this brutal competition system that S-AWC and even Evolution have never-ending motivation.
Mitsubishi Evolution I, equipped with the first generation S-AWC
Mitsubishi Evolution IV with second-generation S-AWC
Mitsubishi Evolution VII, equipped with the third-generation S-AWC
Mitsubishi Evolution X, equipped with the fourth-generation S-AWC
Mitsubishi stopped production of Evolution, the strongest four-wheel drive on the surface has not been upgraded, and the fourth-generation S-AWC. In addition to changing the bevel gear in the rear axle differential of AYC to a planetary gear, it also integrates the major systems of AYC, ACD, ASC, and ABS.
Although the S-AWC of Mitsubishi Evo has nothing new in terms of structural design, it has excellent performance in terms of overall coordination. It is a pity that EVO has faded out of the car arena, and I would like to commemorate it.
Photo and text source: Fengqiao chat car.
