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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.
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