BMW S63

The S63 is the M division’s 4.4-litre twin-turbo V8, in production since 2009. It is
the engine of the M5, M6, M8, X5 M and X6 M, and over that run its output has gone from
553 hp to 627 hp.

What the S63 is

A 4.4-litre petrol V8 with two turbochargers, carrying BMW’s M TwinPower Turbo
branding. It shares displacement with the N63 of the 50i cars
but is the M division’s own engine, with its own cooling, oil supply and state of tune.

The 2014 M6 brochure makes the claim BMW was
willing to put in print at the time: the “4.4-liter V-8 in the M6 Gran Coupe is the most
powerful engine ever fitted into a BMW”. That was true when it was written and has been
overtaken since — by later versions of this same engine.

Where it was fitted

The X6 M row is honest about a gap: our certified records for that car do not carry a
power figure for every model year, so rather than copy the X5 M’s number across we leave
it to the individual specification pages, which show what was
actually certified for each year.

The table stops at 2023 on purpose. For the newest cars our engine-code linkage rests
on BMW’s published fitment lists rather than on the EPA certification code, and those
lists have already proved wrong once in this archive — they put the S63 in the X5 M after
2023, where the certification data shows the S68. Where we cannot resolve the code from
the government record, we do not assert it.

How the output changed

553 hp in the 2013 M5 and M6; 560 hp in the 2014 M6; 567 hp in the X5 M of 2015–2018;
617 hp in the M8 and in the X5 M from 2020; 627 hp in the 2022 M5 CS. The displacement
stays at 4.4 litres throughout, which is why reading the badge tells you almost nothing
and reading the model year tells you almost everything.

What we do not publish

No reliability rating. NHTSA records complaints against a vehicle, not an
engine, so a figure labelled “complaints about the S63” has been arrived at by splitting
a car’s complaints between engines on a guess. What is on this site is what BMW printed
and what the government certified.

Common questions

How much horsepower does the S63 have?

Between 553 and 627 hp in the US-market cars our certified data covers. The 2013 M5
was rated at 553 hp; the 2022 M5 CS at 627 hp.

Which BMWs have the S63?

The M5 from 2013, the M6, the M8, the X5 M and the X6 M. BMW also uses a version of it
in the XM.

What is the difference between the S63 and the N63?

Both are 4.4-litre twin-turbo V8s, but the N63 is the
engine of the non-M cars — 550i, 750i, X5 and X6 xDrive50i — at 400 to 523 hp. The S63 is
the M division’s version, at 553 hp and up, and it goes in the M-badged cars.

Is the S63 still in production?

BMW has continued to build a 4.4-litre M V8 beyond the years in the table, and the
current M5 is a plug-in hybrid rated at 577 hp in our certified data. What we will not do
is tell you which engine code sits in a 2025 car when the government record does not name
it — the non-M 4.4-litre moved to the S68 for 2023, and the M cars followed on a schedule
our data cannot pin down.

Sources

Quotation from the 2014 M6 brochure held in this
archive. Outputs and model years from EPA certification data, with the source named on
every specification page.