What's the difference between VVT and DVVT?

Vvt is a variable valve timing system and DVVT is a variable valve timing system. The biggest difference between them is that VVT engine can only adjust the intake valve, while DVVT engine can adjust the intake valve and exhaust valve at the same time.

VVT (variable valve timing) variable valve timing system. The system adjusts the phase of the engine cam through the equipped control and execution system, so that the opening and closing time of the valve changes with the change of the engine speed, thus improving the charging efficiency and increasing the engine power.

The engine with DVVT technology is more efficient, energy-saving and environmentally friendly than the engine with intake valve timing technology widely used in the market at present. Taking Roewe 550 as an example, DVVT technology can reduce fuel consumption by 5%, and at the same time increase power by 65,438+00%, reaching the power index of 2.0 displacement, and the exhaust emission reaches the national IV standard; By controlling the mixture of gasoline and air in the engine combustion chamber to achieve the most suitable air-fuel ratio, the idling stability can be obviously improved and better comfort can be obtained.