BMW

One of the best diesel engines in the out-of-line brand

As far as powerful diesel engines are concerned, BMW's unit, which combines the 50d versions of Series 5 and 7, in addition to the X5, X6 and X7, is among the best currently proposed. With only 3 litres of capacity, distributed over six cylinders in-line, this motor is necessary because it is equipped with four turbochargers, which provide it with plenty of air.
In fact, the German six quadriturb cylinders uses a double-stage supercharging system, with two low-pressure turbines working together with other high-pressure turbines. The former, with little inertia and ready response, ensure smoothness and progressivity at the low regime, so that the larger turbos provide higher pressure at the high regime, thus extracting more absolute power. With this, BMW succeeded in replacing the old turbodiesel V8, with the advantage of having almost the same power and torque, in a smaller, lighter, cheaper and ... better unit in consumption.
The condemnation of this four-turbos diesel engine is due, according to the statements of a BMW manager to the German publication Auto Motor und Sport, 'to political, social and European market conditions', given that the sales volume of the 50d versions has been losing meaning within the respective ranges. And the reason for this announced death cannot be related to CO2 emissions, because despite providing 400 hp, the 750d announces a consumption of 7.1 litres and 186 g CO2 / km, as against 10.6 l / 100km and 241g CO2 / km of the 750i, with gasoline V8 engine with 530 hp which, curiously, has less force (750 versus 760 Nm) than the diesel version.
BMW claims that the 3.0 quadriturbo-in-line cylinders will exit the European market in the second half of 2020, but will continue to be produced specifically for some countries outside the Old Continent. Only four-cylinder diesel will remain in Europe, with the 50d coming out in 2020 in the production of the 7 Series, and in the 5 Series this will happen only in 2021, when a new generation emerges.

Autonews