NOVELTY - A direct injection internal combustion engine is controlled by calculating output data from system data comprising an injector geometry defined by a fuel injector in fluid communication with a combustion chamber of the engine, an engine geometry defined by the engine, an engine operating command based on a desired engine output, an initial injector command, and an engine speed.    USE - For controlling a direct injection internal combustion engine, particularly useful for gaseous-fuelled direct injection internal combustion engines.    ADVANTAGE - The invention can control and predict engine performance and emissions.    DETAILED DESCRIPTION - Controlling a direct injection internal combustion engine comprises calculating output data from system data comprising:    (a) an injector geometry defined by a fuel injector in fluid communication with a combustion chamber of the engine;    (b) an engine geometry defined by the engine;    (c) an engine operating command based on a desired engine output;    (d) an initial injector command; and    (e) an engine speed.    The engine operating command is indicative of a commanded torque for the engine. The output data comprises an engine out value indicative of a brake torque delivered by the engine, and an output control parameter indicative of a cylinder pressure value. When the output data does not satisfy a predetermined relationship, an injector command is determined and the output data is recalculated with the injector command. The predetermined relationship compares the output data and the engine operating command and a demanded control parameter. The demanded control parameter is indicative of a maximum cylinder pressure value. When the output data satisfies the predetermined relationship, the injector is commanded to provide fuel to the combustion chamber according to a last injector command.    An INDEPENDENT CLAIM is also included for a method of predicting output data generated by a direct injection internal combustion engine. The output data comprises engine torque, fuel consumption, power or cylinder pressure.    DESCRIPTION OF DRAWING(S) - The figure shows a flow diagram of an integrated engine model for use in engine control or predicting engine behavior.