Four stroke engine with a camshaft phasing device

Four-stroke Otto engine comprises one or two inlet valves and one outlet valve per cylinder. The valves of a common camshaft are operated by one adjusting device. The Otto engine is designed so that during early adjustment of the camshafts it operates in an Atkinson cycle. An Independent claim is also included for a process for controlling the above four-stroke Otto engine. Preferred Features: The Otto engine is designed so that during early adjustment of the camshafts the inlet valves close late, preferably at a crankshaft angle of about 40-80degrees after the lower dead point of the piston.