BMW N74

From Wikipedia, the free encyclopedia
BMW N74 engine
2017-09-12 IAA 2017 BMW by Olaf Kosinsky-59.jpg
Model of an N74
Overview
Production2008–present
Layout
Configuration60° V12
Displacement6.0 L (5,972 cc) (2008–2015)
6.6 L (6,592 cc) (2009–2022)
6.7 L (6,749 cc)
Cylinder bore89 mm (3.50 in)
Piston stroke80 mm (3.15 in)
88.3 mm (3.48 in)
90.4 mm (3.56 in)
Block materialAluminium
Head materialAluminium
ValvetrainDOHC with VVT
Combustion
TurbochargerTwin-turbo
Fuel typePetrol
Output
Power output400–465 kW (536–624 hp)
Torque output750–900 N⋅m (553–664 lb⋅ft)
Chronology
PredecessorBMW N73
Cutaway view of N74

The BMW N74 is a twin-turbo V12 petrol engine which replaced the N73 and has been produced since 2008. Production of BMW-branded V12 models will end in 2023.[1] It is BMW's first turbocharged V12 engine and is also used in several Rolls-Royce models.

Design[]

Compared with its naturally aspirated BMW N73 predecessor, the N74 features twin-turbochargers. The turbochargers are located on the outside of the engine and use a boost pressure of 11.6 psi (0.8 bar).[2] In its base configuration the engine has a compression ratio of 10:1 and a specific fuel consumption of 245 g·kW−1·h−1[3]

As per its predecessor, the N74 has direct injection, DOHC and variable valve timing (called double-VANOS by BMW).[4][5] However, the N74 does not have variable valve lift (called Valvetronic by BMW).[6]

The N74 marked BMW's first use of an 8-speed automatic transmission, in the form of the ZF 8HP90.[2]

Versions[]

Engine Displacement Power Torque Year
N74B60[3] 5,972 cc (364.4 cu in) 400 kW (536 hp)
at 5,250 rpm		 750 N⋅m (553 lb⋅ft)
at 1,500–5,000 rpm		 2008–2015
N74B66 6,592 cc (402.3 cu in) 420 kW (563 hp)
at 5,250 rpm		 780 N⋅m (575 lb⋅ft)
at 1,500–5,000 rpm		 2009–2020
465 kW (624 hp)
at 5,600 rpm		 800 N⋅m (590 lb⋅ft)
at 1,500–5,500 rpm		 2013–2022
442 kW (593 hp)
at 5,250 rpm		 840 N⋅m (620 lb⋅ft)
at 1,500 rpm		 2016–2020
N74B66TU 449 kW (602 hp)
at 5,500 rpm		 800 N⋅m (590 lb⋅ft)
at 1,500 rpm		 2016–2022
N74B68 6,750 cc (411.9 cu in) 420 kW (563 hp)
at 5,250 rpm		 900 N⋅m (664 lb⋅ft)
at 1,500 rpm		 2017-present

N74B60[]

This initial version of the N74 has a bore of 89 mm (3.5 in) and a stroke of 80 mm (3.1 in). The redline is 7000 rpm and the compression ratio is 10.0:1.[7]

Applications:

  • 2008–2015 F01/F02/F03 760i/760Li[8]

N74B66[]

N74 in Rolls Royce Ghost

The N74B66 is an enlarged version of the N74B60, due to a stroke of 88 mm (3.5 in). The redline is 7000 rpm and the compression ratio is 10.0:1. It produces up to 465 kW (624 hp) and is used in the Rolls-Royce Ghost.[2]

Year Application Power output Torque
2010–2020 Rolls-Royce Ghost 420 kW (563 hp) 780 N⋅m (575 lb⋅ft)
2014–2020 Rolls-Royce Ghost V-Specification 442 kW (593 hp) 780 N⋅m (575 lb⋅ft)
2014–2022 Rolls-Royce Wraith 465 kW (624 hp) 800 N⋅m (590 lb⋅ft)
2015–2022 Rolls-Royce Dawn 420 kW (563 hp) 820 N⋅m (605 lb⋅ft)

N74B66TU[]

Applications:

N74B68[]

The 6.75 litre version was introduced in the 2018 Rolls-Royce Phantom. It is also used in the Rolls-Royce Cullinan and Rolls-Royce Ghost, both of which are built on the same platform as the new Phantom.[12]

Applications:

References[]

  1. ^ "BMW's biggest engine - the V12 - is safe until 2023". www.topgear.com. Archived from the original on 3 April 2019. Retrieved 4 April 2019.
  2. ^ a b c "2010 BMW 760Li – Second Drive – Car Reviews". www.caranddriver. Archived from the original on 7 July 2017. Retrieved 12 March 2017.
  3. ^ a b Hans-Stefan Braun, Thomas Brüner, Klaus Hirschfelder, Uwe Hoyer, Horst Kellerer, Johann Schopp, Christian Schwarz: Der neue Zwölfzylinder-Ottomotor von BMW Archived 2021-10-06 at the Wayback Machine, in MTZ - Motortechnische Zeitschrift, November 2009, Volume 70, Issue 11, pp. 848
  4. ^ "Information on N74 engines". www.bmwheaven.com. Archived from the original on 6 October 2021. Retrieved 11 August 2017.
  5. ^ 25 years of BMW 12-cylinder engines: setting new standards in the luxury class. Munich, Germany: BMW Corporate Communications. October 2012. Archived from the original on 12 August 2017. Retrieved 11 August 2017.
  6. ^ "BMW N74 engine". www.australiancar.reviews. Archived from the original on 6 January 2017. Retrieved 12 March 2017.
  7. ^ "BMW N73 and N74 V12 Engines". www.unixnerd.demon.co.uk. Archived from the original on 1 October 2017. Retrieved 11 August 2017.
  8. ^ "BMWBLOG Road Review: 2013 BMW 760Li – The Power of 12". www.bmwblog.com. Archived from the original on 6 October 2021. Retrieved 11 August 2017.
  9. ^ "The new BMW M760Li xDrive". www.bmwgroup.com. Archived from the original on 12 August 2017. Retrieved 11 August 2017.
  10. ^ "Watch BMW's twin turbo all wheel drive V12 G11 M760li hustle to 162 miles per hour". www.bimmerboost.com. Archived from the original on 12 August 2017. Retrieved 11 August 2017.
  11. ^ "BMW N74B66TU / M760li xDrive". www.drive2.ru (in Russian). Archived from the original on 6 October 2021. Retrieved 11 August 2017.
  12. ^ "RealOEM.com - Online BMW Parts Catalog". www.realoem.com. Archived from the original on 20 November 2017. Retrieved 20 November 2017.
Retrieved from ""