2.5 "N52B25" Engine [e.g. BMW 3 E46]

The BMW E46 2.5 (engine code: N54B25) is a petrol engine built by BMW that was used in several E46 3 Series models. It has a displacement of 2494 cm³ and produces around 192 hp (141 kW) with 245 Nm of torque. The engine is fitted with twin turbochargers and reaches its maximum torque as early as 2000 rpm. Performance is excellent, with 0–100 km/h taking around 6.5 seconds.

The N54B25’s technical specifications are impressive. It features two turbochargers that improve both performance and fuel economy. In the twin-turbo setup, the smaller turbo spools up first, allowing the larger turbo to then be fed with airflow. This significantly improves throttle response and low-end torque. The engine also has direct fuel injection, which improves fuel economy and reduces emissions.

The N54B25 is well engineered, and its components are high quality throughout. Aluminium and magnesium are used in its construction, reducing weight and improving cooling. The cylinder heads also feature a highly durable Vanos variable valve timing system, which boosts engine performance and cuts emissions.

The BMW E46 2.5 engine (N54B25) is a high-performance, technically advanced unit that delivers excellent power and torque, making it a firm favourite among car enthusiasts. Its quality components and innovative design make it a reliable, long-lasting choice.

The BMW E46 2.5 engine was used in many E46 3 Series models, including the BMW 325i, 325xi and 325Ci. The N54B25 was also used in BMW’s X3 and Z4 models.

The exact engine shown in the photo may no longer be available, but we always send our quote together with photos and full details — including mileage and general condition — of the engine currently in stock.

Which cars does this engine fit?

Engine code N52B25 was fitted to models including: BMW 3 E46. The list is indicative — the same engine may also have been used in other models from the same manufacturer.

Always check your own engine code before ordering. The same displacement and the same model name can mean a different engine in a different model year, and only the code tells you for certain which engine the car has.

Where do I find the engine code?

The engine code is usually in one of three places:

• The registration document — under engine type or engine number.
• The engine itself — cast or stamped into the block, often at the gearbox end or under the cover.
• A workshop — a garage reads the code from your VIN in the manufacturer’s catalogue in a couple of minutes.

If you cannot find the code, send us the VIN and the registration number with your enquiry and we will look it up for you.

Request a quote for this engine

Every engine we sell is tested and comes with a warranty. Most of our stock never appears on the website, so do ask for an engine that is not listed.

Send your enquiry with the engine code or the VIN and you will have an answer within 24 hours.