BMW M42
| BMW M42 | |
|---|---|
| Overview | |
| Manufacturer | BMW |
| Production | 1989–1996 |
| Layout | |
| Configuration | Naturally aspirated straight-4 |
| Displacement | 1.8 L (1,796 cc) |
| Cylinder bore | 84 mm (3.31 in) |
| Piston stroke | 81 mm (3.19 in) |
| Cylinder block material | Cast iron |
| Cylinder head material | Aluminium |
| Valvetrain | DOHC |
| Compression ratio | 10.0:1 |
| Combustion | |
| Fuel system | Fuel injection |
| Fuel type | Petrol |
| Chronology | |
| Predecessor | BMW M40 |
| Successor | BMW M44 |
The BMW M42 is a DOHC straight-four petrol engine which was produced from 1989-1996. It is BMW's first mass-production DOHC engine and was produced alongside the BMW M40 SOHC four-cylinder engine as the higher performance engine.
The M42 was replaced by the BMW M44, which was introduced in 1996.
Compared with the M40, the M42 features a DOHC valvetrain, a timing chain, hydraulic valve lifters and an increased 10.0:1 compression ratio. Later versions of the M42 also feature a dual length intake manifold ("DISA").
The M42 was used as the basis for the S42 racing engine, which powered the BMW 320i in the German Super Tourenwagen Cup.