BMW S54 Engine

The S54 Engine is one of the best ever! Used in the BMW E46 M3, the BMW
M Z3 Roadster, M Z3 Coupe, M Z4 Roadster and M Z4 Coupe. Voted International
Engine of the Year and class winner of Engine of the Year for 3 straight years!


The S54 powerplant revs to a maximum of 8,000 rpm, puts into practice know-how

such as Double VANOS variable valve timing and cross-flow cooling for the
cylinder head. Known within BMW as the S54, this 24-valve powerplant boasts
365Nm at 4,900rpm and benefits from a bespoke engine management system with two
32-bit microprocessors that perform 25 million calculations per second. The
longitudinally
mounted M Sport-developed engine also has race-car-like throttle
response.
The S54 shares its format with other BMW inline 6-cylinder engines. Virtually all of its
engineering details, however, are unique and oriented to the very highest level
of
performance. Given that other current BMW “sixes” have an aluminum block
with cast-iron
cylinder liners, it may be surprising that the S54 engine has a
cast-iron block. Why?

Compactness is the primary reason. An inline six is longer than a V-6, and BMW
nurtures the inline layout because of its superior smoothness and sound. An
aluminum block’s cylinder liners take up space; with liners it would not have been
possible to achieve the engine’s 3.2-liter displacement without lengthening the block.
The second reason is strength. Given that this engine develops a fully 333 hp from
3.2 liters – significantly over 100 hp per liter – its internal stresses are immense.

The S54 engine has stepless Double VANOS , which varies valve timing on the intake and
exhaust camshafts. Though Double VANOS is employed in current 3, 5, X5 and Z4 Series
6-cylinder engines, in the M Z4 engine, it varies timing over a wider range and contributes
in a major way to the engine’s stratospheric power output. Intake
timing is varied
by 60°, exhaust by 46°, vs. 40° and 25°, respectively. As in all BMW
engines where it is
employed, VANOS is hydraulically actuated in response to
electronic controls.