BMW N74
Introduction Cutaway view of N74The '''BMW N74''' is a twin-turbo V12 petrol engine which replaced the N73 and has been produced since 2008.It is BMW's first turbocharged V12 engine and is also used in several Rolls-Royce models.
Design The N74 features twin turbochargers, which are not present on its naturally aspirated BMW N73 predecessor. The turbochargers are located on the outside of the engine and use a boost pressure of . In its base configuration the engine has a compression ratio of 10:1 and a specific fuel consumption of 245 g·kW−1·h−1Like its predecessor, the N74 has direct injection, DOHC and variable valve timing (called double-VANOS by BMW). However, the N74 does not have variable valve lift (called Valvetronic by BMW).The N74 marked BMW's first use of an 8-speed automatic transmission, in the form of the ZF 8HP90.
Versions EngineDisplacementPowerTorqueYearN74B60    at 5,250 rpm    at 1,500–5,000 rpm  2008–2015N74B66    at 5,250 rpm   at 1,500–5,000 rpm  2009–2020  at 5,600 rpm    at 1,500–5,500 rpm 2013–2022  at 5,250 rpm    at 1,500 rpm 2016–2020 N74B66TU    at 5,500 rpm    at 1,500 rpm 2016–2022 N74B68      at 5,250 rpm    at 1,500 rpm 2017–present=== N74B60 ===This initial version of the N74 has a bore of  and a stroke of . The redline is 7000 rpm and the compression ratio is 10.0:1.Applications:* 2009–2015 F01/F02/F03 760i/760Li=== N74B66 ===N74 in Rolls Royce GhostThe N74B66 is an enlarged version of the N74B60, due to a stroke of . The redline is 7000 rpm and the compression ratio is 10.0:1.It produces up to  and is used in the Rolls-Royce Ghost. Year  Application  Power output  Torque 2010–2020  Rolls-Royce Ghost     2014–2020  Rolls-Royce Ghost V-Specification    2019Eadon Green Panthean Coupe 2014–  Rolls-Royce Wraith     2015–  Rolls-Royce Dawn    === N74B66TU ===Applications:* 2016–2022 G12 M760Li xDrive===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.Applications:* 2017–present Rolls-Royce Phantom VIII* 2018–present Rolls-Royce Cullinan* 2021–present Rolls-Royce Ghost
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