BMW BLENDS TURBOS INTO A 4,6 SEC­OND FUN RUN

The Witness - Wheels - - MOTORING - — Wheels Re­porter.

BMW HAS an­nounced its TwinPower Turbo tech­nol­ogy, which fea­tures not two but four tur­bocharg­ers and the latest tech in com­mon-rail di­rect in­jec­tion.

This multi-stage tur­bocharg­ing sys­tem was en­gi­neered for the BMW 750d xDrive and BMW 750Ld xDrive, and makes 294 kW and 760 New­ton me­tres to qual­ify as the world’s most pow­er­ful six-cylin­der diesel en­gine.

Yet, BMW also claim fan­tas­tic fuel con­sump­tion — a com­bined use of as low as 5,7 l/100 km — and very low CO2 emis­sions of be­tween 154 and 149 g/km.

Bear­ing in mind the on­go­ing VW and Mit­subishi emis­sion scan­dals, BWM would have been very care­ful to have ver­i­fied these fig­ures.

BMW also claims ac­cel­er­a­tion from zero to 100 km/h in 4,6 sec­onds for the heavy 750d xDrive, a claim which ev­ery petrol­head is sure to test.

BMW’s en­gi­neers said in a state­ment this “get up and go” is due to a new form of multi-stage tur­bocharg­ing, “which now brings to­gether four tur­bocharg­ers to en­able boost pres­sure to be built up even more quickly at lower en­gine speeds and there­fore prompts swift re­sponses to throt­tle ap­pli­ca­tions from idle”.

In nor­mal driv­ing, the two low-pres­sure tur­bocharg­ers and one of the two high-pres­sure turbos are per­ma­nently in ac­tion.

Only un­der hard ac­cel­er­a­tion from idle will the two low-pres­sure tur­bocharg­ers be by­passed by means of a flap con­trol sys­tem. This al­lows boost pres­sure to be built up even more quickly. The sec­ond high-pres­sure tur­bocharger is brought into play at an en­gine speed of about 2 500 rpm.

An­other new fea­ture is ex­haust gas re­cir­cu­la­tion for the low-pres­sure stage of the tur­bocharg­ing sys­tem as well as the high-pres­sure stage.

This in­creases the ef­fec­tive­ness of the tur­bocharg­ers and of the en­gine as a whole.

PHOTO: BMW

The BMW 750d xDrive — the most pow­er­ful six­cylin­der diesel — will be on sale from July 2016.

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