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.

The Toyota A Series engines are a family of inline-four internal combustion engines with displacement from 1.3 L to 1.8 L produced by Toyota Motor Corporation. The series has cast iron engine blocks and aluminum cylinder heads. To make the engine as short as possible, the cylinders are siamesed.