General Motors Co. confirms today plans to build a pair of next-generation 4-cyl. Ecotec engines at its Tonawanda, NY, powertrain plant, a new-product commitment totaling $494 million across three facilities and adding 56 jobs.

To prepare for the new engines, GM will invest $425 million at Tonawanda for a capacity of 370,000 engines and create 470 jobs.

The auto maker recently terminated production at Tonawanda of a big-block V-8, indefinitely laying off some 150 people, and a V-6 engine that comprised a majority of its output. The Buffalo-area plant employs some 650 people, with a reported 375 on indefinite layoff. During the late-1980s and early 1990s, 4,000 people worked at the 72-year-old facility.

New hires reportedly will begin at the lower end of GM’s new 2-tier pay scale.

GM also puts $59 million into its Defiance, OH, powertrain plant to support precision sand cast blocks for the engines at a capacity of 188,000 annually. Defiance will hire 80 people, the auto maker says.

GM’s Bay City powertrain plant will receive a $10.5 million investment to produce connecting rods for the engines and will add 15 jobs.

GM provides few details about the new engines, citing competitive reasons, but says the motors will build upon its current-generation Ecotec architecture featuring gasoline direct-injection, variable-valve timing and turbocharging technologies.

The spokeswoman for the auto maker also declines providing a timetable for production of the new engines.

A 2.4L version of the engine, which currently powers the Chevy Equinox and GMC Terrain Cross/utility vehicles, Buick LaCrosse premium sedan and upcoming Buick Regal sports sedan, earned a Ward’s 10 Best Engines nod this year.

In the Equinox and Terrain, the 2.4L achieves an Environmental Protection Agency-rated and segment-leading 32 mpg (7.4 L/100 km) on the highway. GM says the next-generation Ecotec engines will see even greater fuel efficiency and performance with additional technology.

The 2.4L engines, as well as a 3.0L version, launched with the ’10 model year, joining existing 2.0L and 2.2L displacement mills.