BMW S54B32
 |
|
| Manufacturer | BMW M GmbH |
|---|---|
| Production | 2001–2008 |
| Predecessor | BMW S50B32 |
| Configuration | Straight-6 |
The S54B32 was a high-performance engine used in BMW M vehicles. The block was made from grey cast iron rather than aluminum to achieve greater rigidity from the same dimensions. It is a 3.2 L (3246 cc) engine; bore is 87 mm (3.4 in) and stroke is 91 mm (3.6 in). It has reinforced forged steel connecting rods, graphite coated cast aluminum pistons and a forged steel crankshaft.
The S54 is the final, most powerful evolution of the M50 engine line, incorporating individual throttle bodies, drive-by-wire throttle control, and variable valve timing (VANOS) for both intake and exhaust camshafts.
At launch the non-US versions fitted to the E46 M3 produced 343 hp (256 kW) at 7900 rpm, with 269 ft·lb (365 Nm) of torque at 4900 rpm and a 8000 rpm redline. The US version required some modifications to meet US emissions standards (such as close-coupled catalytic converters closer to the engine exhaust ports) and thus produced slightly less power in each application. In addition, air intake and exhaust differences, as well as a lower RPM limit, resulted in different performance figures for the Z3 M Roadster and Z3 M Coupé.
BMW also produced an even more powerful version of the S54B32, for the limited edition E46 M3 CSL. This engine lacked a conventional mass airflow meter, and BMW installed modified intake and exhaust camshafts, as well as a more efficient air intake system. This version yielded 360 hp (270 kW) at 7900 rpm with 273 lb·ft (370 N·m) of torque at 4300 rpm.
The S54 won the International Engine of the Year award overall for 2001, and also claimed the "Best New Engine" that year as well as won the 3-4 L category for six straight years in a row from 2001 through 2006. The S54 was also on the Ward's 10 Best Engines list for 2001 through 2004.
Despite its great success and critical acclaim, the S54 was plagued with rod bearing failures in early production. BMW attempted to blame vehicle owners for the failures early on but eventually started replacing rod bearings, oil pumps, and whole engines under warranty. This fault was attributed to a problem with the connecting rod bottom-end bearing shells that were supplied to BMW by a third party that did not meet BMW's specifications. This problem was fully corrected by BMW on engines produced after 06/2003. A recall was issued to retrofit all M3 cars with affected engines to swap to the proper bearing shells. The recall did not include M Roadster or M Coupe cars with affected S54 engines due to the lower RPM limit.
BMW has since retired the S54 engine, but it is still used by Wiesmann for their MF3 Roadster.
| Application | Displacement | Power | Torque | Redline | Stroke | Bore | Compression |
|---|---|---|---|---|---|---|---|
| US Z3 M Coupé, Z3 M Roadster | 3.2L (3246 cc/198 in³) | 235 kW (315 hp) @ 7400 | 340 N·m (251 lb·ft) @ 4900 | 7600 | 91 mm (3.58 in) | 87 mm (3.43 in) | 11.5:1 |
| US E46 M3, E85 Z4 M Roadster, E86 Z4 M Coupé | 3.2L (3246 cc/198 in³) | 248 kW (333 hp) @ 7900 | 355 N·m (262 lb·ft) @ 4900 | 8000 | 91 mm (3.58 in) | 87 mm (3.43 in) | 11.5:1 |
| Non-US Z3 M Coupé, Z3 M Roadster | 3.2L (3246 cc/198 in³) | 239 kW (325 hp) @ 7400 | 353 N·m (261 lb·ft) @ 4900 | 7600 | 91 mm (3.58 in) | 87 mm (3.43 in) | 11.5:1 |
| Non-US E46 M3, E85 Z4 M Roadster, E86 Z4 M Coupé | 3.2L (3246 cc/198 in³) | 256 kW (343 hp) @ 7900 | 365 N·m (269 lb·ft) @ 4900 | 8000 | 91 mm (3.58 in) | 87 mm (3.43 in) | 11.5:1 |
| E46 M3 CSL | 3.2L (3246 cc/198 in³) | 265 kW (355 hp) @ 7900 | 360 N·m (273 lb·ft) @ 4900 | 8000 | 91 mm (3.58 in) | 87 mm (3.43 in) | 11.5:1 |
[edit] Applications
- 2001-2006 E46 M3
- 2001-2002 Z3 M Roadster
- 2001-2002 Z3 M Coupé
- 2006-2008 E85 Z4 M Roadster
- 2006-2008 E86 Z4 M Coupé
- 2002-.... Wiesmann Roadster MF3
