Honda B engine
The B-series are a family of inline four-cylinder DOHC automotive engines introduced by Honda in 1989. Sold concurrently with the D-series which were primarily SOHC engines designed for more economical applications, the B-series were aimed more as a performance option featuring dual-overhead cams along with the first application of Honda's VTEC system (available in some models). To identify a Honda B-series engine, the letter B is normally followed by two numbers to designate the displacement of the engine, another letter, and in US-spec engines, another number. The Japanese spec-engines are normally designated with a four character alphanumeric designation. The B-series, the B20B variant in particular, is not to be confused with the earlier Honda B20A engine introduced in 1985 and primarily available in the Prelude and Accord-derived vehicles from 1985-1991. While sharing some design elements and both being multivalve Honda four-cylinders, the B-series and B20A differ substantially in architecture, enough to be considered distinct engine families.