BMW’s New Engine Has Four Turbochargers

And it’s a diesel. 

byMax Prince|
BMW’s New Engine Has Four Turbochargers

Three is better than two, just like two is better than one. That’s the conventional wisdom, at least, disseminated everywhere from Ecclesiastes to the Arby's drive-thru menu. Evidently, BMW's into that whole thing, too. Not contented with its current triple-turbo “N57S” engine, the luxury automaker has unveiled its next-gen diesel motor. And, yeah, this puppy’s got four turbochargers.

The announcement comes from the Vienna Motor Symposium, undoubtedly the most German-sounding event in the history of Germany and possibly events. Like the outgoing tri-turbo engine, the new “B57” is a straight-six with 3.0 liters of displacement. Peak output is 394 horsepower, on tap from 4000 to 4400 rpm. Torque, as you’d expect from a diesel engine with four turbos, is healthy—561 pound-feet, available between 2000 and 3000 revs. And that’s not even exploiting the full potential; engineers had to cap the torque to keep from destroying the automatic gearbox. Because four turbos.

Technically speaking, the B57 retains BMW’s two-stage forced induction system. But whereas the old engine used a single low-pressure turbo for grunt and two high-pressure turbos in upper revs, the new engine replaces the bigger turbo with two smaller guys on a common exhaust. The result, according to BMW, is five percent better fuel economy and, because of some clever packaging, a negligible weight penalty. It also allows owners to tell everybody that their car has four freakin' turbochargers

The new engine will make its first appearance in the flagship 7-Series sedan. BMW says that, equipped with the quad-turbo six-cylinder, an all-wheel drive 750d will do 0-60 mph in 4.5 seconds. Don’t be surprised to see the B57 in the next wave of M Performance models, too, specifically the X5 and X5 SUVs, as well as the next 5-Series. Sadly those models will almost certainly be verboten in the U.S. market.