New single turbo with twin-scrolls extends the torque band with 400 Nm of peak torque reached at 1,200 rpm. The engine, referred to internally at BMW as the N55, also comes with High Precision (Direct-)Injection and VALVETRONIC variable valve...
Here's a detail of the new BMW 535i Gran Turismo that deserves to be duly noted.
The 535i GT features BMW's new TwinPower Turbo with High Precision Injection and VALVETRONIC technology, a single turbo with twin-scrolls that puts the squeeze on the 3.0 liter straight-six gasoline engine, internally referred to as the N55 over at BMW.
This engine, as opposed to the twin turbochargers of the N54 version, is a first for BMW, coupling that single twin-scroll turbo with High Precision Injection and the variable valve management of the VALVETRONIC system. The 4.4 liter V8 that goes into the 550i GT still gets a twin-turbo but that 4.4 liter may be getting this new tech-upgrading for the upcoming X5M/X6M versions.
Distinguishing the N55's performance from its predecessor includes a broadening of the torque band, the 400 Nm now peaking pretty early at 1,200 rpms, and extending all the way to 5,000 rpms. The N55 also has a map-controlled oil pump which helps conserve energy, a first for a turbocharged engine, and the improved engine management gives it a better fuel economy and CO2 emission rating than the N54.
Naturally, speculation goes to the obvious next step, that BMW will introduce VALVETRONIC and High Precision (Direct)-Injection on a twin-turbo version of this 3.0 liter straight-six and dial the horsepower up to 360.