An engine system includes an engine having an intake manifold and a turbocharger that supplies compressed air to the intake manifold. An engine control module calculates a desired pre-throttle pressure of air before the throttle and calculates a desired manifold air flow into the engine. The engine control module determines a desired pre throttle pressure area based on the desired air per cylinder, desired manifold pressure and RPM and generates control signals to control the engine with the turbocharger.