Mitsubishi has released the first details on its next generation 1.8 liter gasoline engine codenamed "4J10" that incorporates a new version of the company's MIVEC variable valve timing system. The new engine also marks the introduction of a new Auto Stop & Go (AS&G) idle-stop technology. The new 4J10 four cylinder petrol with AS&G techology will make its debut in Japan this month on the domestic market RVR, Galant Fortis and Galant Fortis Sportback. This will be followed by the international variants of the aforementioned models.

Mitsubishi says that with this combination, the three models show a 12% improvement in fuel efficiency in the Japanese 10-15 mode driving cycle. One of the most important features of the new 1.8-liter engine is the latest iteration of the company's MIVEC system that continuously regulates intake valve lift, opening duration and timing. Before the 4J10, Mitsubishi employed two types of MIVEC systems - one that switches between different valve lifts and valve opening durations according to engine speed; another that varies the valve opening timing on a continuous basis. The new MIVEC system combines the above 2 systems. In JDM specification, the 1.8 liter SOHC unit is rated at 139hp at 6000 rpm and 172Nm at 4,200 rpm. The specs are comparable to Honda