DETROIT (AP) — Shares of Westport Innovations Inc. surged 9 percent Wednesday after the maker of natural-gas engine technology announced a deal with General Motors Co.

The Vancouver, British Columbia, company said it was working with GM on two different approaches to natural gas engine combustion, controls and emissions. Another project was announced in June of last year.

Westport's stock price jumped $2.95, or 9 percent, to $35.45 a share in late-morning trading. GM shares rose 1 cent to $19.86.

Natural gas is appealing because it costs less than gasoline, and it's abundant in the U.S. It produces fewer greenhouse gas emissions than traditional gasoline or diesel.

GM has said it will sell natural-gas powered versions of two pickup trucks, the Chevrolet Silverado and GMC Sierra 2500 HD, late this year. The GM trucks will run on gasoline and natural gas for 650 miles.

Its Detroit rivals offer natural-gas vehicles. Chrysler will sell a Ram 2500 Heavy Duty pickup that runs on natural gas starting in July. Ford has offered natural-gas ready pickups and vans since 2009.

Westport said it has opened a technical center in Plymouth, Mich., near Detroit to help automakers with natural gas engine technology. It also has opened a factory in Louisville, Ky.