Shanghai, July 03: General Motors plans to ramp up output at its main carmaking joint venture in Shanghai, the company said on Wednesday, joining an expansion race among foreign firms that analysts fear could foment a damaging glut. The China Daily reported on Wednesday GM would invest 2bn yuan ($240m) to double capacity at an existing five-year old plant in Shanghai, raising maximum output by an additional 100,000 cars a year. The venture’s board had already approved the building of a factory to open by ’05, said an executive at Shanghai Automotive Industry, GM’s partner in the $1.5bn joint venture. Bureau Report