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 and a
stroke of [except for the Chinese market and a
stroke of ].
2012 technical update In 2012, a "Technical Update" was applied to the N63, resulting in the
N63TÜ 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.
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 ==