The 2.0-liter Honda B20A was produced from 1985 to 1991 and powered the second- and third-generation Prelude, as well as the Accord and Vigor of the third generation outside the USA. Despite the similar name, it is not related to the later B-series engines such as the B20B.
The block is a closed-deck aluminum casting with thick cast-iron sleeves. The best-known versions have a 16-valve DOHC head and PGM-FI injection: the early “Gold Top” B20A produced up to 160 PS (JIS gross), later ones 135-145 hp. The B20A3 and B20A4 have a simpler 12-valve SOHC head with two carburetors and about 110-115 hp. In the third-generation Prelude the engine is tilted 18 degrees towards the firewall to allow a very low hood line.
The B20A family also includes: B21A.
Specifications
| Production years | 1985-1991 |
| Displacement, cc | 1958 |
| Fuel system | carburetor / injector |
| Power output, hp | 109 – 160 |
| Torque output, Nm | 150 – 186 |
| Cylinder block | aluminum R4 |
| Block head | aluminum 12v / 16v |
| Cylinder bore, mm | 81 |
| Piston stroke, mm | 95 |
| Compression ratio | 9.2 – 9.4 |
| Features | SOHC / DOHC |
| Hydraulic lifters | no |
| Timing drive | belt |
| Phase regulator | no |
| Turbocharging | no |
| Fuel type | petrol |
The engine was installed on:
- Honda Prelude 2 (AB) in 1985 – 1987;
- Honda Prelude 3 (BA) in 1987 – 1991;
- Honda Accord 3 (CA) in 1985 – 1989 (Japan, Europe);
- Honda Vigor 1 (CA) in 1985 – 1989 (Japan).
Disadvantages of the Honda B20A engine
- Being an old and rare engine, many spare parts are hard to find;
- Carburetor versions need competent adjustment of the twin carburetors;
- The timing belt must be replaced on schedule;
- At this age oil leaks from the valve cover and distributor seals are common.
