Evernham Motorsports. The engine failures of both Earnhardt and Truex were attributed in part to the lack of a lead additive, but also to centrifugal force causing improper distribution of oil between the left and right sides of the engine. Evernham Motorsports has not disclosed the reason behind Kahne's engine failure. The 2008 season marked the first season all 36 races used unleaded racing fuel. 2011 marked one of the largest "green initiatives" in the fifty plus year history of NASCAR when all fuel sources were to include Ethanol in a blend called E15. One unintended consequence of the conversion was higher horsepower and therefore slightly lower fuel economy. It is argued however, that the reduction in fuel economy and the resultant increase in fuel use may offset any environmental impact savings by reduced emissions. Although not connected to the fuel blend, a new "Dry Break" self-venting fuel supply can was also adopted in part for safety (reduced the number of people working on the racecar during a pit stop) but also in part to reduce the amount of fuel spilled during a pit stop, which has both environmental and safety implications. In 2012 a complete technology change and shift in thinking occurred when NASCAR switched the Monster Energy NASCAR Cup Series to fuel injection from the current carburetor. Arguments have been made about increased efficiency; however, race teams will work to ensure they take advantage of the additional horsepower and efficiency to increase speeds so any improvement in efficiency may be lost to competition. Today, the entire motorsports industry invests significant development costs in increasing fuel conception and moving towards net zero emissions in response to climate change. Participation of non-American manufacturers NASCAR's early history included several foreign manufacturers, such as Aston Martin, Austin-Healey, Citroën, Jaguar, MG, Morgan, Porsche, Renault, and Volkswagen. At a 1954 road race in Linden, New Jersey, Jaguar cars finished first, fourth, fifth and sixth. As a matter of policy, NASCAR restricted entry to American car makers from the 1960s until 2004, when Toyota was allowed to enter the NASCAR Craftsman Truck Series with the Toyota Tundra. The restriction was relaxed in recognition of the fact that the Tundra, while Japanese in origin, is built in the United States. (Toyota had previously competed in Goody's Dash Series, winning the title in 2003 prior to their entry to Truck Series; various foreign makes have also competed