Over the weekend, at the Vienna Engine Symposium, BMW unveiled its much rumoured quad-turbo straight-six diesel engine.
The quad-turbo engine features four exhaust-driven turbochargers, with two high pressure units allied to two low pressure devices. Rumours had earlier suggested this new engine might feature an electrically driven compressor to help out at low engine speeds.
According to Bimmerpost, the new 3.0-litre engine will be used first in the 750d xDrive and will replace the company’s tri-turbo 3.0-litre straight-six. For the executive express, the new motor develops 294kW of power between 4000 and 4400rpm, and 760Nm of torque between 2000 and 3000rpm.
That’s an increase of 14kW and 20Nm over the outgoing N57 tri-turbo 3.0-litre, which was rated 280kW and 740Nm.
The Kronen Zeitung quotes Fritz Steinparzer, head of diesel engine development at BMW, as saying that the quad-turbo engine can develop more torque than its present 760Nm rating, but that the company had to limit the engine’s output due to the eight-speed ZF 8HP automatic transmission that it’s paired with.
In its present form, the new engine is good enough to haul the 750d xDrive from 0-100km/h in 4.6 seconds and an electronically limited top speed of 250km/h. Fuel consumption for this car, under the EU cycle, is said to be 5.8L/100km.