A method of controlling intake and exhaust cam phase in an internal combustion engine for optimal HVAC performance in a motor vehicle includes requesting a cabin heating value, sensing an engine speed and an engine load of the internal combustion engine, utilizing the cabin heating value, the engine speed and the engine load in one or more lookup tables to determine intake phaser constraint values and exhaust phaser constraint values for cabin heating, and transitioning the intake phaser constraint values and the exhaust phaser constraint values for cabin heating to intake phaser constraint values and exhaust phaser constraint values based on one or more lookup tables for normal operation without a cabin heating request.