N52 Engine

Specifications

The BMW N52 engine is a naturally aspirated inline-six petrol engine produced from around 2004 to 2011, known for its lightweight magnesium-aluminum composite block, smooth operation, and advanced technology. It features a DOHC 24-valve layout with Double VANOS (variable cam timing) and Valvetronic variable valve lift, eliminating the need for a traditional throttle body under most conditions. 

The engine was offered mainly in 2.5-liter and 3.0-liter displacements, producing roughly 174–272 hp and 230–315 Nm of torque depending on the variant, with a rev limit of about 7,000 rpm. Widely used across BMW models such as the E90 3 Series, E60 5 Series, Z4, and X3, the N52 is praised for its linear power delivery, refinement, and efficiency for a naturally aspirated six-cylinder engine.  

Engine Variants

N52B25 (2.5L)

The BMW N52B25 is a 2.5-liter naturally aspirated inline-six petrol engine designed mainly for European and other international markets. It features a lightweight magnesium-aluminum engine block, DOHC configuration with four valves per cylinder, BMW’s Double VANOS variable camshaft timing, and Valvetronic variable valve lift for improved efficiency and throttle response. Depending on the specific tune and market, it produces approximately 174 to 201 horsepower, offering smooth power delivery and good fuel efficiency. This engine was commonly installed in models such as the BMW 125i, 525i, and Z4 2.5i.  

N52B30 (3.0L)-Standard Output

The standard-output N52B30 is a 3.0-liter naturally aspirated inline-six and was the most common version sold in North America. Like the B25, it uses a magnesium-aluminum composite block, Double VANOS, and Valvetronic technology. In this configuration, the engine typically produces around 215 to 228 horsepower, balancing performance with reliability and everyday drivability. It was used in models such as the BMW 328i, 528i, X3 2.5si/3.0si, and Z4 3.0i. 

N52B30 (3.0L)-High Output

The high-output version of the N52B30 is the most powerful naturally aspirated variant in the N52 lineup. It includes a three-stage DISA intake manifold and revised valvetrain components (often referred to as “diesel-style” valves) to improve airflow and high-rpm performance. These upgrades allow the engine to produce approximately 258 to 272 horsepower, delivering strong mid-range torque and a higher revving character. This version was fitted to performance-oriented models such as the BMW 330i, 530i, 630i, X5 3.0si, and Z4 3.0SI.  

Frequently Asked Questions