VVT-i

VVT-i

◆ VVT-i (Variable Valve Timing-intelligence) is an engine variable valve technology registered by Toyota, namely "intelligent variable valve timing system". The biggest feature is that the intake camshaft can be controlled according to the state of the engine, and the valve timing can be optimized by adjusting the camshaft angle to obtain the best valve timing, thereby increasing the torque in all speed ranges. And it can improve fuel economy to a certain extent, effectively improve the power and performance of the car, and reduce fuel consumption and exhaust emissions.

◆ VVT-i is composed of sensors, electronic control units, hydraulic control valves and controllers, etc., and is divided into two types according to the installation position of the controller: one is installed on the exhaust camshaft, called vane VVT-i , such as the Toyota King; the other is installed on the intake camshaft, called the spiral groove VVT-i, Lexus 400, 430 and other high-end cars are using this form.

◆ The ECM of the Toyota VVT-i engine automatically searches for an optimal valve timing corresponding to the engine speed, intake air volume, throttle position and cooling water temperature under various driving conditions, and controls the camshaft timing hydraulic control valve. The actual valve timing is perceived through the signals of various sensors, and then feedback control is performed to compensate system errors and achieve the optimal valve timing position, thereby effectively improving the power and performance of the car and minimizing fuel consumption and exhaust emissions.

◆ Engine variable valve timing technology is one of the new technologies that have been gradually applied to modern cars in recent years. The engine adopts variable valve timing technology to increase the intake charge and increase the charge coefficient. Engine torque and power can be further increased.