VVT-i, or Variable Valve Timing with intelligence, is an automobile variable valve timing technology developed by Toyota. It was introduced in 1995 with the 2JZ-GE engine found in the JZS155 Toyota Crown and Crown Majesta.

The Toyota ZZ engine family is a straight-4 piston engine series. The ZZ series uses a die-cast aluminium engine block with thin press-fit cast iron cylinder liners, and aluminium DOHC 4-valve cylinder heads. The camshafts are chain-driven. The two 1.8 L members of the family, the 1ZZ and 2ZZ, use different bore and stroke. The former was optimised for economy, with torque emphasised in lower revolutions per minute operating range, while the latter is a "square" design optimised for high-RPM torque, yielding higher peak power. The ZZ family replaced the extremely popular cast-iron block 4A engines.