GM High-Tech Performance Blogs
Computer-controlled valvetrain technology?
Drivers of the 2014 Chevrolet Impala coming early next year can get improved fuel economy over the competition due in part to a new advanced valvetrain technology on the Ecotec 2.5L four-cylinder engine.
Chevrolet’s redesigned flagship sedan uses new Intake Valve Lift Control (IVLC) technology that enables variable intake valve lift, duration and timing over a wide range of engine operation. When the technology operates in low-lift mode, the engine pumps only the air it needs to meet the driver’s demand. The system switches to high-lift mode at higher speeds or under heavy loads, providing the full output capability of the engine.
“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. “What they will notice is a fuel savings of up to one mile per gallon.”
The engine achieves variable valve lift using an innovative all-new rocker arm that switches between low and high lift intake cam profiles. The mechanism is actuated by an oil control valve through a dual-feed stationary hydraulic lash adjuster. It is the first of its kind for low friction roller-type finger-follower valvetrains in gasoline engines. The engine’s computer continuously selects the optimal lift profile based on conditions such as engine speed and load.
Impala’s three powertrains all feature fuel-saving direct injection and lightweight components.
Impala’s Ecotec 2.4L engine works with the eAssist system to provide electrical assist in certain conditions to help save fuel. It is GM-estimated at 182 horsepower (134 kW) and 35 mpg on the highway.
The Ecotec 2.5L is one of a new family of four-cylinder engines developed with increased efficiency and greater refinement. Output is estimated at 195 horsepower (145 kW).
As a lover of high performance GMs, you may be wondering why this is significant. Well with the specifics on the upcoming Gen V V-8 still under wraps, this begs the question whether similar technology will be used on the small-block Chevy. Stay tuned for the answer.