The Ecotec family line up of engines has played a rather important role in General Motors’ history and when the 2014 Chevrolet Impala hits, a new chapter will begin. In 2.5 liter form, the inline four cylinder will utilize an all-new valvetrain system that should deliver some of the segment’s best fuel economy numbers. Chevrolet’s new Intake Valve Lift Control is an improved variable timing system that operates at peak efficiency for a wide variety of engine revolutions.
“Intake Valve Lift Control works so seamlessly drivers aren’t likely to notice it at all,” said Mike Anderson, GM global chief engineer for Ecotec engines. The system enables variable intake valve lift, duration and timing for all types of engine speeds and loads. For example, in low-lift mode such as low-speed cruising, the intake valves only allow in the air needed for a driver’s demand. This not only increases reliability, but boosts fuel savings in the process. The only time high-lift mode is activated is when a driver calls for all of the engine’s 195 horsepower.
In order to achieve this accomplishment, Chevrolet engineers installed an all-new rocker arm assembly for the 2.5 Ecotec’s valvetrain. An oil control valve mitigates the various lift modes via a stationary hydraulic lash adjuster. The Impala’s ECU is ultimately responsible for controlling the system and constantly monitors driver inputs to fully optimize the engine’s efficiency.
Source: Chevrolet