What are the differences between N54 and N55?

[OAlexis]

Here are the differences between N54 and N55: 1. Turbocharging: The N54 features twin turbos with two different-sized turbos engaging at different RPMs to counteract turbo lag, while the N55 uses a single twin-scroll turbo, distributing the turbo's power among three cylinders. 2. Displacement: The N55 incorporates BMW's signature Double VANOS continuously variable valve timing, resulting in better fuel efficiency than the N54 at the same displacement and horsepower. Although costs aren't reduced, the N55's drawback is that future modifications aren't as straightforward as with the N54. Due to its excessive torque, the X6M cannot use ZF's 8-speed transmission and instead employs a 6-speed dual-clutch transmission. Despite having two fewer gears, its shifting speed far surpasses that of a regular X6.