Tumble flap

This swirling motion improves the air-fuel mixture and enhances power and torque, while at the same time lowering fuel consumption and decreasing emissions.

The set point of the tumble flap is adjusted by an electrical or vacuum-activated servo mechanism which is under the control of the engine management system.

In gasoline direct injection, stratified charge mode is used for light-load running conditions, at constant or reducing road speeds, where no acceleration is required.

The so-called "tumble plate" divides the air inlet channel into an upper and lower half.

[2] At higher engine speeds and torques, the tumble flap is opened to achieve a better degree of filling.