The BMW N63 is a twin-turbocharged petrol V8 engine which has been in production from 2008 to present. The N63 is the world's first production car engine to use a "hot-vee" layout, with the turbochargers located inside the "V" of the engine. It is also BMW's first turbocharged petrol V8 engine. The engine has been widely noted for its mechanical issues, undergoing several recalls. The N63 replaced the BMW N62 (a naturally aspirated V8 engine) and was first used in the 2008 X6 xDrive50i. The S63 engine is the BMW M high-performance version of the N63. Alpina versions of the N63 are used in various F01 7 Series, F10 5 Series, G11 7 Series, G15 8 Series and G30 5 Series models.

Design

The airflow path through the engine uses a "hot-vee" layout, where the exhaust manifolds and turbochargers are located between the cylinder banks (on the "inside" of the V8) and the intake manifolds are located on the outside of the engine. This is opposite to the traditional layout for a V8, where the intake is inside the "V" and the exhaust manifold is on the outside. The hot-vee layout reduces the width of the engine and decreases the exhaust runner length from the exhaust valves to the turbochargers. The engine uses air-to-water intercoolers, therefore improving throttle response. Similar to the N54B30, the initial N63 (including the S63) did not use Valvetronic (variable valve lift) because its benefit of reducing of intake vacuum is not as important in turbocharged engines. Due to the presence of turbocharging, the N63 does not use a variable-length intake manifold. The N63 is BMW's first V8 engine to use direct injection. The N63/S63 uses a bore of 89 mm and a stroke of 88.3 mm [except for the Chinese market 89 mm and a stroke of 80 mm].

2012 technical update

In 2012, a "Technical Update" was applied to the N63, resulting in the N63TU variants (also known as N63B44O1). The main upgrade was the addition of Valvetronic. Other changes include revised turbochargers, removal of the blowoff valve, lighter pistons, forged connecting rods and crankshaft, addition of a valve cover labyrinth oil catch/return system, new valve stem seals, revised fuel system and addition of a second coolant pump.

2016 technical update

A second Technical Update occurred in 2016, resulting in the N63TU2 variants (also known as N63B44O2). The major changes are the use of twin-scroll turbochargers, a wider powerband and the oil/coolant heat exchanger being moved to within the "V" of the engine.

2018 technical update

A third Technical Update was introduced in 2018. Two variants are offered: N63B44M3 and N63B44T3. N63B44M3 features improved thermal shielding for the crankcase and the cylinder head, and a new ignition system. The N63B44T3 gains higher pressure (5000psi) injectors, larger twin-scroll turbochargers, a redesigned intake manifold, and an upstream cooling radiator.

Models

N63B40A

This smaller variant was sold in the Chinese market. Due to a shorter stroke length of 80 mm, the capacity is reduced to 3982 cc. Applications:

N63B44O0

The initial version of the N63 produces 300 kW and 600 Nm. Applications:

N63B44O1 (N63TU)

The first technical update resulted in an increase of 31 kW and 50 Nm. Applications:

N63B44O2 (N63TU2)

The second technical update resulted in peak torque being produced over a 200 rpm wider band. Applications:

N63B44M3 (N63TU3)

Applications:

N63B44T3 (N63TU3)

Applications:

S63

The S63 is the BMW M version of the N63, which debuted in the BMW X6 M and was used in the BMW M5 models from 2011 to 2023. The S63 uses two twin-scroll turbochargers plus a pulse tuned, cross-engine exhaust manifold to keep constant exhaust pulses flowing to the turbos at every 180 degree rotation.

S63B44T4

Applications:

S63B44O0

Applications:

S63B44T1

A technical update to the S63, known as the S63B44T1, debuted on the F10 M5 sedan. This version uses Valvetronic, a 10:1 compression ratio (compared with 9.3:1 for the non-TU version) and 1.5 bar of boost (compared with 1.3). It is the first BMW M engine to use Valvetronic. The rev limit was increased from 6800 rpm to 7200 rpm. Applications:

S63B44T2

The S63B44T2 debuted on the 2015 X5 M and X6 M models. Applications:

S63B44T4

The S63B44T4 debuted on the 2018 M5. Applications:

P63

The P63 is the BMW Motorsport version of the N63, which debuted in the BMW M8 GTE.

Alpina

Alpina uses a variant of the N63 engine, which was hand-assembled at the Alpina plant in Buchloe before being transported to the BMW production line. For the 2013 model year, the Alpina engine received Valvetronic like all other N63 engines.

M1

Applications:

M1/1

Applications:

M1/2

Applications:

M2, M2/1

Applications:

M2/2

Applications:

M5

The Alpina engine code is N63M30A. Applications: An evolution of this engine, with better power delivery, is of the N63B44T3 type. Applications:

North American recall

In December 2014, BMW North America released a voluntary recall ("Customer Care Package") relating to issues with timing chain stretch, fuel injectors, mass air flow sensors, crankcase vent lines, battery, engine vacuum pump, low pressure fuel sensor and revising the oil service interval. In 2019 NHTSA addressed the multitude of issues with BMW N63 engines, various class action lawsuits in tow, and never officially declared a mass recall in regard to valve seal issues inherent in the N63 line.