What is the principle of downshifting to accelerate?

[EvangelineLynn]

Introduction to downshifting for deceleration is as follows: 1. Downshifting to overtake: This refers to the need to downshift when overtaking with a car, which yields better results. The moment the gear is shifted up, the engine speed immediately decreases, but the vehicle speed remains unchanged. At the same time, due to the reduction in the transmission ratio, the torque output from the engine to the wheels also decreases. After the upshift is completed, the car accelerates through the throttle, but due to the reduced torque output, the car's speed slows down. The moment the gear is shifted down, the engine speed immediately increases, but the vehicle speed remains unchanged. Simultaneously, with the increase in the transmission ratio, the torque output from the engine to the wheels also increases. 2. After the downshift is completed: The car will decelerate by reducing the throttle (so-called deceleration and downshifting). Because the torque output becomes larger, continuing to increase the throttle at this time will generate a significant acceleration for the car, causing it to accelerate rapidly, thereby meeting the needs of overtaking.