History of the diesel car and considerably lighter than the in-line six-cylinder it also replaced, this 3.0L V-6 produces 165 kW (224 hp) at 3,800 rpm and max torque of 510 Nm (376 ft·lbf) at 1,600-2,800 rpm and makes use of a four-valve head. Additionally, fitment of Mercedes-Benz BlueTec system, a concert of emissions control strategies, renders this new diesel 50-state legal in the U.S. beginning in 2008 (stringent NOx limits have made U.S. passenger-car diesels unpopular or impossible in parts of the U.S. in recent years). In 2006, the new Audi R10 TDI LMP1 entered by Joest Racing became the first diesel-engined car to
Bilevel rail car by diesel locomotives and include electric generators housed in the control car. In Iran, the Tehran-Hashtgerd suburban commuter line is served with electric push-pull hauled trainsets with double-decker carriages manufactured by Wagon Pars in Iran. In South Korea, ITX-Cheongchun, the express train of Korail uses double-decker. Because of the two levels being separate on most cars, there is a physical limitation on a single conductor, as it can be difficult for him or her to verify, collect payment and sell tickets to passengers on the two levels. In 1955, the St. Louis Car Company came up with a solution in