S54 engine

Specifications

The BMW S54 engine is a 3.2-liter (3,246 cc) naturally aspirated inline-six engine produced by BMW M between 2000 and 2008, most notably powering the E46 M3 as well as the Z3 M and Z4 M models. Designed with a strong motorsport focus, it uses a cast-iron engine block for durability paired with a lightweight aluminum cylinder head, a DOHC 24-valve valvetrain, and BMW’s dual VANOS variable valve timing system on both the intake and exhaust camshafts. One of its defining features is the use of six individual throttle bodies, which deliver exceptionally sharp throttle response and high-rpm breathing, supported by a semi-dry-sump lubrication system to ensure consistent oil supply during aggressive driving. 

With an 11.5:1 compression ratio, the S54 produces between 333 and 360 horsepower at up to 7,900 rpm and 262–273 lb-ft of torque, depending on the version, while revving to an 8,000-rpm redline. Celebrated for its high-revving character, linear power delivery, and distinctive sound, the S54 is widely regarded as one of the finest naturally aspirated inline-six engines ever produced by BMW M.  

Engine Variants

S54B32 (Standard)

The standard S54B32 powered the E46 M3, Z3 M Roadster/Coupe, and later the Z4 M models, delivering a high-revving and motorsport-inspired driving experience. In U.S. specification, it produced 333 hp (252 kW) at 7,900 rpm and 262 lb-ft (355 Nm) of torque at 4,900 rpm, while European versions made 343 hp, with slightly lower output in early Z3 M applications. Its combination of dual VANOS, individual throttle bodies, and an 8,000-rpm redline made it one of BMW M’s most celebrated naturally aspirated engines.  

S54B32HP (CSL)

Built exclusively for the E46 M3 CSL, the S54B32HP was a higher-performance evolution of the standard engine, optimized for reduced weight and improved airflow. It featured a carbon-fiber intake plenum, revised camshafts, and a modified exhaust system, raising output to 360 hp (265 kW) and 273 lb-ft (370 Nm) of torque. These enhancements sharpened throttle response and top-end power, reinforcing the CSL’s track-focused character.

S54B32 (Z4 M Variant)

The S54 used in the Z4 M Roadster and Coupe retained the same core architecture and performance characteristics as the standard version but was adapted to suit the Z4 chassis. Changes included a revised oil pan and exhaust layout, along with minor regional tuning differences, while maintaining the engine’s signature high-revving nature and strong, linear power delivery.  

Frequently Asked Questions