Fuel-Efficiency | GM’s 2.5 Ecotec Engine

GM’s 2.5 Ecotec promises the best of all worlds.

Owners of the new 2014 Chevrolet Impala, equipped with the Ecotec 2.5L four-cylinder engine, might be surprised by how quiet and how eager the engine is. GM engineers have been tweaking this Ecotec powerplant, and the results promise to be impressive.

The key technology on the 2.5L Ecotec is something GM is calling “Intake Valve Lift Control Technology.”  Think of it as GM’s version of VTEC (Honda). Intake Valve Lift Control Technology allows the valves to open and close by varied amounts and at different times (depending on power demand) to provide greater fuel efficiency or power.

This technology has two settings: low-lift and high-lift. In low-lift mode, the engine lets in only the air it needs to meet the driver’s demand. In high-lift mode, all the engine’s ponies are readily available to the driver. High-lift mode kicks in under heavy loads.

GM engineers have designed the 2.5L Ecotec with a rocker arm that switches between low-lift and high-lift intake cam profiles. The engine’s computer continuously selects the optimal lift profile based on driving conditions and driver demand.

GM engineers also made this Ecotec powerplant, “one of the quietest and most refined in the segment,” by adding a sound-absorbing cover to the intake manifold, using quieter drive chains, relocating the balance shafts from the cylinder block to a spot within the oil pan, and employing active noise cancelling technology.

Finally, they say this Ecotec engine is one of the most fuel-efficient they’ve ever built. Quieter, more responsive, and more fuel-efficient – that’s quite the hat-trick. Impala owners are sure to be impressed!

Source: http://torontosun.autonet.ca/2013/05/24/powerful-quiet-and-fuel-friendly