Hayman Capital Management, the Dallas hedge fund run by investor Kyle Bass, has taken a stake in General Motors, betting that it will appreciate as the U.S. government winds down its ownership stake, according to a person familiar with the matter.“Detroit is back. And GM could lead the way forward on the equity front,” Hayman said in a presentation published on the website HVST.com. “GM equity represents one of the most compelling risk/reward situations of any large cap in the world today.” The largest U.S. automaker, which operates an assembly plant in Arlington and a finance division in Fort Worth, should increase in value by more than 40 percent in 12 to 18 months, Hayman Capital said in the presentation. The GM stake is one of its largest investments, said the person, who asked not to be identified because the matter is private. Hayman declined to disclose the size of its stake. The Treasury expects to sell its remaining 31.1 million GM common shares by year’s end, depending on market conditions, the government said last month. The sale would cap almost half a decade of government oversight after GM’s 2008 bailout and 2009 bankruptcy. Bass, who made a name for himself with his prescient bet against subprime home mortgages before the financial crisis, said the U.S. exit is a trigger for GM stock. “The U.S. government will be out of the way before the end of the year,” Bass said in a telephone interview. “They’ve been a source of constant selling pressure in the equity this year.” Analysts project that the automaker will generate $5.4 billion in free cash flow in 2014, double last year’s figure. A push to give shareholders some of its cash, built up during the government-backed bankruptcy and restructuring, would clash with some of CEO Dan Akerson’s goals to maintain spending on new products and buy back preferred shares left after the bankruptcy. Shares of Detroit-based General Motors (ticker: GM) rose 57 cents to close at $38.71 Wednesday after reaching a record of $39.62. The stock has gained more than 30 percent this year, outpacing the Standard & Poor’s 500. “A strong case can be made that GM should trade at a premium to the [automotive] group,” Hayman said. Bolstering that investment argument are the company’s “unique position and strong underlying fundamentals, a best-in-class leverage to global growth markets, improving operational efficiency from ongoing turnaround efforts and an improving product cadence.” Dave Roman, a GM spokesman, declined to comment on Hayman’s investment in the company. Bass, who is not related to Fort Worth’s Bass family, focuses on corporate turnarounds. He racked up billions in profits by betting against subprime mortgages while the world’s largest financial institutions wrote off more than $80 billion in subprime losses.He has about $2 billion under management, owning securities ranging from secured debt and shares in Plano-based J.C. Penney to Argentina’s restructured bonds. He has been betting on a Japanese fiscal collapse for years and on gold as a hedge against inflation spurred by central banks printing money.Confidence in GM has grown as the Treasury sells its stake, helping facilitate a return to the S&P 500. The automaker is introducing 18 new or refreshed vehicles this year in the U.S. and 14 next year as it transforms its lineup into one of the freshest in the industry from among the oldest.