Battling to catch up with German rivals in China, luxury carmaker Daimler is shifting gears, giving local authorities unprecedented access to new Mercedes models and even tailoring engines destined for its home market to Chinese regulations. For years, Daimler has lagged Audi (VOWG_p.DE) and BMW (BMWG.DE) in the world’s biggest car market. Last year, Mercedes-Benz, the company’s premier luxury brand, sold 228,000 cars there, compared to nearly 492,000 for Audi and over 362,000 for BMW. For years, Daimler harbored doubts over the sustainability of growth in China.