Is the BMW N54B30 engine twin-turbo or single-turbo?

[HavenFitz]

N54B30 is a 3.0L twin-turbocharged engine that incorporates almost all technologies BMW could offer for an engine except turbocharging. To comply with stricter emission regulations while meeting consumers' demands for driving pleasure, BMW introduced the N54 twin-turbo engine in 2007, marking the beginning of its turbocharging journey. More details are as follows: 1. The 3.0L twin-turbo N54B30 engine comes in various tuning versions to match different BMW models. The highest-power version delivers 335 horsepower (250kW) at 5900rpm and 450N·m at 1500-4500rpm. 2. The N54 engine evolved from the exceptionally well-designed naturally aspirated inline-six N52 engine from 2001, which utilized nearly all BMW engine technologies except turbocharging, achieving best-in-class performance. Building upon N52's excellent and mature design, the N54 added two small-diameter turbochargers and introduced advanced direct fuel injection technology, significantly improving power output compared to N52. 3. BMW engineers conducted extensive experimental work on the N54 engine, resulting in substantial power gains. The two small-diameter turbos can spool up at lower RPMs, giving the N54 nearly instantaneous throttle response similar to naturally aspirated engines. However, the twin-turbo design made the N54's intake/exhaust systems relatively complex and necessitated the removal of BMW's advanced Valvetronic electronic valve technology. The N54 engine represents BMW's bold attempt and innovation in turbocharging technology.