See the New 2020 BMW 7-Series Plug-In Hybrids

While BMW engineers tend to express themselves best through their finished automotive products, the technical preview of the new 745e proved that they also do a good line in onomatopoeic phrases. While you won’t find it in any German dictionary, the company’s engineering team refer internally to the thrashy sound of an overworked engine as knurrij. Their understandable aversion to this is much of the reason for the big change that sits under the hood of the facelifted 7-Series plug-in hybrid.

We have grown used to BMW’s numerical sleight of hand in recent years; “30” used to denote a model fitted with one of the company’s smooth, muscular 3.0-liter inline-sixes, but it now designates a brawnier version of the company’s considerably less creamy 2.0-liter four-banger.

The new 745e, set to come to the United States this spring as part of the 7’s midlife upgrade, is a substantial departure from the current 740e thanks to the arrival of a new six-cylinder engine in place of the outgoing car’s frequently overworked 2.0-liter four.

The engineering team behind the 745e is careful not to be too critical of the 740e but admits that the smaller engine didn’t provide the effortless performance that people expect from the upper reaches of the 7-series range-thanks to that car’s excess of knurrij.

To better make the point, C/D went to Bavaria to experience both the 740e and a prototype version of the new 745e back to back, both on the company’s test track at Maisach, near Munich, and on local roads, including a section of the famous autobahn network without a speed limit.

BMW’s modular powertrain architecture means that each side of the 745e’s hybrid system is familiar. The gasoline engine is the turbocharged 3.0-liter inline-six that powers almost all of the company’s mid-range models, in a relaxed state of tune producing 280 horsepower.

The synchronous electric motor that sits between this and the transmission is effectively unchanged from that in the 740e, contributing up to 111 horsepower for a combined output of 389 ponies, a significant improvement over the 322 horses that the 740e mustered.

The e-motor produces up to 195 lb-ft and the maximum combined effort is 442 lb-ft.

As tends to be the case with the generational shift of electric powertrains, the big developments have taken place within the battery system.

The lithium-ion pack sits beneath the rear seats and boasts a capacity of 12.0 kWh-up from 9.2 kWh for the dimensionally similar unit in the 740e, thanks to improved energy density.

While we don’t have official EPA estimates yet, BMW predicts an electric-only range of around 31 miles (50 km) under the European testing protocol. We can safely predict the EPA range estimate will be shorter, but it will be some weeks yet before we get an official figure.

European buyers will be offered rear-wheel drive and standard wheelbase models, but all the cars coming to America are all-wheel drive on the longer wheelbase.

We also aren't offered the M-sport trim that puts an M logo on the front fenders of the European models in the accompanying photos.

While BMW has already told us that it is looking to future hybrid systems that will electrify one axle of a car while using internal combustion to power the other, the 745e-and the rest of the company’s next-gen plug-in systems-continue to use a blended system with the electric motor sitting upstream of the ZF-supplied eight-speed automatic gearbox.