Understanding BMW Engine Names (Engine Naming System Explained)

✔ This article has been fact checked.

M10 stood for a four-cylinder engine, M20 for a small six-cylinder engine, and M30 for a big six-cylinder engine. But as more BMW engines were being designed, a different identification system was required.

The current format dates from the middle of the 1980s. BMW engine codes are intended to convey a information about the technology and design of the engine in a condensed amount of space.

"M", "N", or "B" codes are used with standard BMW engines. An "S" code is used for BMW M performance production motorsport engines. A "P" code is used by the official BMW motorsport engines.

The identification system changes depending on which engine it is. Using the guides below can help decipher the meaning BMW engine names.

Table of Contents:

• "S" Engine Code

• "M" Engine Code

• "N" Engine Code

• "B" Engine Code (2020 Version)

• "B" Engine Code (2023 Version)

• BMWs Engine Naming System

BMW "S" Engine Code

In the example below, the S85B50, using the engine naming system we can decipher this engine is a BMW production motorsport 5.0 litre V10 petrol engine.

Engine Family (First Letter)

M - standard engines (1991-2005)

N - standard "New Gen" engines (2006-2016)

B - standard modular engines (2016+)

S - BMW Motorsport production engine

P - BMW Motorsport non-production engine

W - engine shared with another manufacturer

Cylinder Count (First Number)

Engine Variant (Second Number)

Fuel Type (Second Letter)

Displacement (Last Two Numbers)

BMW "M" Engine Code

For this example, we will use the M62B44TU. Using the identification system below we can decipher this BMW engine is a pre 2006 standard road engine, 2nd version, 4.4 litre V8 with a technical update.

Engine Family (First Letter)

M - standard engines (1991-2005)

N - standard "New Gen" engines (2006-2016)

B - standard modular engines (2016+)

S - BMW Motorsport production engine

P - BMW Motorsport non-production engine

W - engine shared with another manufacturer

Cylinder Count (First Number)

Engine Variant (Second Number)

Fuel Type (Second Letter)

Displacement (Last Two Number)

Technical Update (TU)

BMW "N" Engine Code

For this example, we will use the N55B30T0. Using the identification system below we can decipher this BMW engine is a first design "new gen", inline six-cylinder TVDI, 3.0 litre petrol engine in the top power level.

Engine Family (First Letter)

M - standard engines (1991-2005)

N - standard "New Gen" engines (2006-2016)

B - standard modular engines (2016+)

S - BMW Motorsport production engine

P - BMW Motorsport non-production engine

W - engine shared with another manufacturer

Cylinder Count (First Number)

Technical Highlight (Second Number)

Fuel Type (Second Letter)

Displacement (Third & Fourth Number)

Power Level (Third Letter)

Revision (Fifth Number)

BMW "B" Engine Code (2020 Version)

For this example, we will use the B46B20O0. Using the identification system below we can decipher that this BMW engine is an original design 2016+ modular engine, four-cylinder TVDI & SULEZ, 2.0 litre longitudinal petrol engine in the upper power level.

Engine Family (First Letter)

M - standard engines (1991-2005)

N - standard "New Gen" engines (2006-2016)

B - standard modular engines (2016+)

S - BMW Motorsport production engine

P - BMW Motorsport non-production engine

W - engine shared with another manufacturer

Cylinder Count (First Number)

Technical Highlight (Second Number)

Fuel Type / Engine Layout (Second Letter)

Displacement (Third & Fourth Number)

Power Level (Third Letter)

Revision (Fifth Number)

BMW "B" Engine Code (2023 Version)

For this example, we will use the B58B30O1. Using the identification system below we can decipher that this BMW engine is a second update of the 2016+ modular engine, inline six-cylinder TVDI, 3.0 litre longitudinal petrol engine in the upper power level.

Engine Family (First Letter)

M - standard engines (1991-2005)

N - standard "New Gen" engines (2006-2016)

B - standard modular engines (2016+)

S - BMW Motorsport production engine

P - BMW Motorsport non-production engine

W - engine shared with another manufacturer

Cylinder Count (First Number)

Technical Highlight (Second Number)

Fuel Type / Engine Layout (Second Letter)

Displacement (Third & Fourth Number)

Power Level (Third Letter)

Revision (Fifth Number)

BMW also still uses the "TU" suffix, but with no direct link to the naming code system. Some engines are also paired with an electric motor, it's not clear if the naming code system will change to accommodate hybrid powertrains.

BMWs Engine Naming System

Unexpectedly, BMW does not always adhere to its own guidelines. Although we have mentioned a number of engine codes above, there may be further variations not listed.

Up to the S63 engine in 2009, S engine codes essentially follow the format of the M engine key. The S engines closely follow the corporate code key from the N engines after the S63.

The PHEVs (Partial Hybrid Electric Vehicles) use an extra powertrain code. Although we are yet to see a key explaining the code, it will begin with "XB1".

The "XB1" designation is currently mostly meaningless when looking for engine components because all PHEV cars employ an extra electric battery and motor in addition to a standard B-series engine.

Sometimes you'll notice engine codes that don't match the keys mentioned above; this is generally a shortened abbreviation of the code.

The "N52N" is frequently mentioned. For some reason, BMW decided to add a N in 2007.

The N52K and N52O engines found in 2006 models are slightly different, we assume they intended to distinguish it from them. As an example, BMW will occasionally use an N63TU engine key rather than an N63T1 engine key.

A Technical Update (TU) stands for a major update or new engineering feature. We can only assume that this is a holdover from the time when major upgrades were denoted by a "TU" suffix under the M code, and BMW still sometimes uses it.

Sources