The new RB20 engine series comprises in-line, 6-cylinder, 2-liter gasoline engines with an all-new design that succeed the L20 engine (1)*, whose performance has been upgraded numerous times since it was first released 20 years ago.The RB20 engine series includes a single-overhead-cam (SOHC) engine and a double-overhead-cam (DOHC) engine, each of which also has a turbocharged version, making a total of four different engine variations. This range of variations is intended to meet the broad, diversified needs of today's market.The main development theme set for the new engine family was to achieve “improved performance that would appeal to the senses”. Thus emphasis was not merely put on obtaining high performance figures, but on making real improvements in engine response and quietness that the driver could actually feel.This paper focuses on two of the four engine variations - the DOHC engine with and without a turbocharger. It discusses the basic engine construction, principal component parts and major development objectives. In the discussion that follows the DOHC engine without a turbocharger is referred to as RB20DE and the turbocharged DOHC engine is referred to as RB20DET.