Continuously variable valve lift system including valve deactivation capability on one of two dual intake valves

In a dual intake valve arrangement for an internal combustion engine, a continuously variable valve lift (CVVL) system controls two intake valves for one or more engine cylinders. In each cylinder, one of the intake valves includes an associated valve deactivation device, and the other intake valve does not. To improve in-cylinder air flow turbulence under low valve lift, one of the intake valves may be deactivated, resulting in mixture intake through only one valve, resulting in strong swirl by unbalanced flow. A CVVL-equipped engine including a valve deactivation device provides the same amount of air flow for the same engine load as a prior art CVVL engine. A method of introducing a swirl to the mixture is also described.