The B20 engine produced from 1996 to 1998 has 126 horsepower, and the B20 model produced from 1998 to 2001 has 146 horsepower. These engines were designated as B20B and B20Z. A B20A model was produced from 1985 to 1989, but it has a different design from the regular B20B/Z.
The B20 engine is basically a non-VTEC B18 with overbored pistons to 84 millimeters. Since the B20 design is the same used with the B16 and B18 model, this engine is often modified by having placed the B16 or B18 VTEC valve train on its short block, since it has a bigger displacement of 1,973 cubic centimeters.