The 2012 Dodge Caliber will be powered by a Fiat-designed 1.4-liter turbocharged 4-cylinder engine with the Italian company’s advanced MultiAir valve-control system. This powerplant debuts in the BMW Mini-fighting Alfa Romeo MiTo 2-door hatchback that’s due to start U.S. sale for model-year 2011. MultiAir is the big deal here. Basically, it uses valve lifters operated by an electrohydraulic mechanism that can adjust valve timing and valve lift through virtually infinite steps for each cylinder and at each stage of the four-stroke combustion cycle. This contrasts with electromechanical systems like Honda’s VTEC that vary timing and/or lift for all valves through only two or three fixed modes. Fiat claims MultiAir improves fuel economy by 10-15 percent over a conventional engine of comparable size while increasing power by a like amount. The company also touts a 15-25 percent reduction in CO2 emissions and a 60-percent drop in levels of hydrocarbons and NOx (oxides of nitrogen).
