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, 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.
Frequently asked questions about the Honda B20A
How much power does the Honda B20A make?
The Honda B20A develops 109 - 160 hp and 150 - 186 Nm of torque.
Does the Honda B20A have a timing belt or chain?
The Honda B20A uses a timing belt.
Is the Honda B20A turbocharged?
No, the Honda B20A is naturally aspirated.
Does the Honda B20A need valve clearance adjustment?
Yes, there are no hydraulic lifters, so the valve clearances have to be checked and adjusted periodically.
What cars was the Honda B20A installed on?
Honda Prelude 2 (AB) in 1985 - 1987, Prelude 3 (BA) in 1987 - 1991; Honda Accord 3 (CA) in 1985 - 1989 (Japan, Europe); Honda Vigor 1 (CA) in 1985 - 1989 (Japan).
What are the common problems of the Honda B20A?
Being an old and rare engine, many spare parts are hard to find. Carburetor versions need competent adjustment of the twin carburetors. All known problems.
What engines are related to the Honda B20A?
The B20A family also includes: B21A.
