The E0 series is a three-cylinder gasoline engine developed and manufactured by Honda, with a total displacement of 656 cc. The engine is intended for kei car applications. The E05A and E07A were partially replaced by the Honda P engine but as of 2020 the E07Z engine still saw use in the Acty truck. The E0 is based on the Honda EH Engine, a SOHC 2-cylinder engine. Like the Honda D engine, it rotates anti-clockwise from the timing belt side. The engine was available with either a computer-controlled variable venturi-type side draft carburetor (PGM-CARB) or a multi-point fuel-injected (PGM-FI) version. Utilizing a cross-flow design, the intake and exhaust valves are opened and closed by the rocker arm driven by a camshaft timing belt. The two intake and two exhaust valves are positioned on either side of the spark plug which is mounted on the top center of the combustion chamber. The cylinder block and cylinder bore are made of die-cast aluminum, as are the valve covers and oil pan. Early Japanese emissions requirements for passenger automobiles required that exhaust gas purification be accomplished by means of a three-way catalyst. The requirement was later amended to include commercial vehicles as well.