General Motors Co. will invest $483 million in its Tennessee plant and call back 483 workers to ramp up production of 4-cylinder Ecotec engines, the company said Friday.

The deal, however, is contingent on GM securing state and local incentives.

The Detroit automaker said the commitment would bring the total amount of new U.S. investment since its emergence from bankruptcy to $2.9 billion, including the creation or retention of 7,417 job across 20 plants.

The jobs will come from a pool of laid-off workers in according with company’s labor agreement with the United Auto Workers.

“The engines made in Spring Hill (Tenn.) will drive the success of GM to meet our customer demands for advanced powertrains which offer high fuel economy without sacrificing performance,” said Mark Reuss, head of GM North America.

He said the investment will help GM nearly triple its North American production volume of direct-injection 4-cylinder engines  by 2012. The plant builds the Ecotec engine used in vehicles including the Chevrolet Equinox, Buick LaCrosse and GMC Terrain.

The spending plan includes $23 million and 30 jobs toward ramping up production of the current Ecotec with the rest used for the next generation.

The stamping plant, which employs 1,045, ships some 100,000 parts  to seven GM assembly plants a week.

The investment doesn’t affect the assembly lines at the Spring Hill facility, idled in the wake of GM’s bankruptcy last year after having  turned out Saturn models and the Chevy Traverse.