BMW S54

The S54 is the M division’s 3.2-litre naturally aspirated inline-six, built from 2000
to 2008. It is the engine of the E46 M3, and the last M3 six before the M division moved
to a V8 — which is most of the reason people still look it up.

What the S54 is

A 3.2-litre straight-six with no turbocharger, individual throttle bodies and
Double-VANOS variable valve timing. The 2004 M3
brochure lists the hardware without adjectives: a “3.2-liter dual overhead cam (DOHC),
24-valve inline 6-cylinder engine with Double-VANOS ‘steplessly’ variable valve timing”
and “6 individual throttles, electronically controlled (drive-by-wire).”

Six throttle bodies rather than one is the detail that matters. It is expensive and it
exists to sharpen throttle response — the same arrangement the M division carried over to
the V8 that replaced this engine, where the count went to eight.

Where it was fitted

In the United States the S54 was an M3 engine and nothing else, at 333 hp for every
model year our specification pages carry. BMW also used it in the
Z3 M and Z4 M, and in a lower state of tune outside the US market; those cars are not in
this archive’s certified data.

S54 or S65

They are the two ends of one decision. The S54 is a 3.2-litre six making 333 hp; the
S65 that replaced it for 2008 is a 4.0-litre V8 making 414 hp.
Same car, same badge, an extra 81 hp and two more cylinders. If you are looking at an M3
from 2006 or earlier it has the six; from 2008 onwards, the V8.

What we do not publish

No reliability score, and for a specific reason. The NHTSA complaint database files
problems against a vehicle, not an engine, so “complaints about the S54” is a
figure nobody can compute honestly — a 2004 M3 and a 2004 330i sit in different buckets,
but a 2019 3 Series with three different engines sits in one. What we publish is what BMW
printed and what the government certified.

Common questions

How much horsepower does the S54 have?

333 hp in the US-market E46 M3, for every model year from 2001 to 2006. European
versions were rated slightly differently under a different standard.

Which BMWs have the S54?

In the United States, the E46 M3 Coupe and Convertible. Worldwide, also the Z3 M Coupe
and Roadster and the Z4 M.

Is the S54 turbocharged?

No. It is naturally aspirated, with six individual throttle bodies rather than forced
induction. The first turbocharged M3 engine was the S55 of
2015.

What replaced the S54?

The S65, a 4.0-litre naturally aspirated V8, from the 2008
M3 onwards.

Sources

Engine hardware and quotations come from the 2004 M3
brochure held in this archive. Outputs and model years come from EPA certification
data; each specification page names its source for every figure.