The Detroit Diesel Series 60 is an inline-6 four-cycle Diesel engine that was first produced in 1987. It departed from most on-highway engines, by being an overhead camshaft engine and having full "drive by wire" electronic control. In 1993 it became popular on many Charter buses in the US at 11.1 L (677 cu in). In 1993, the 11.1 L (677 cu in) version was rated at 350 bhp (260 kW) (but would produce 15 more if the cruise control was engaged).