Editing W engine (section)

{{Short description|Type of reciprocating engine}}
[[File:Napier Lion W12 @ Brooklands Museum.JPG |thumb |right |[[Napier Lion]] W12 aircraft engine (circa 1930) ]]

A '''W engine''' is a type of [[piston engine]] where three or four [[cylinder (engine)|cylinder]] banks share the same [[crankshaft]], resembling the letter "W" when viewed from the front.<ref name="Wiley1936" /><ref>{{cite book |last= Taylor|first= Charles Fayette|orig-year= 1968|year= 1985|title= The Internal-combustion Engine in Theory and Practice: Combustion, fuels, materials, design|url= {{Google books|mX1-OJBQ6ngC|The Internal-combustion Engine in Theory and Practice: Combustion, fuels, materials, design|page=241|plainurl=yes}}|publisher= [[Massachusetts Institute of Technology]]|isbn= 0-262-70027-1|lccn= 84028885|access-date= 2013-12-17|quote= W engine is similar to a V engine but with three banks of cylinders. The two V angles are usually equal.}}</ref><ref>{{cite book |last= Rajput|first= R. K.|date= December 2005|title= Internal Combustion Engines|url= {{Google books|UtxI5gXM1yQC|Internal Combustion Engines|page=37|plainurl=yes}}|location= New Delhi, India|publisher= Laxmi Publications|isbn= 817008637X|access-date= 2013-12-17|quote= W-engine Same as V-engine except with three banks of cylinders on the same crankshaft.}}</ref>

W engines with three banks of cylinders are also called "broad arrow" engines, due to their shape resembling the British government [[broad arrow]] property mark.<ref name="Wiley1936">{{cite book |last1= Domonoske|first1= Arthur Boquer|last2= Finch|first2= Volney Cecil|year= 1936|title= Aircraft engines: theory, analysis, design, and operation|url= https://books.google.com/books?id=qrc7AAAAMAAJ&q=%22broad+arrow%22+W|type= Engineering textbook|publisher= J. Wiley & Sons|page= 7|access-date= 2014-04-25|quote=The W, or broad arrow engine, has three rows of cylinders of which the central row is vertical with the other two rows forming equal angles with the vertical.}}</ref><ref name="NewSunbeam32">{{Citation |url= https://books.google.com/books?id=GlApAQAAIAAJ&q=Broad+arrow&pg=PA32 |title=The New Sunbeam Overhead Valve Type Engines| magazine= Aviation Week and Space Technology |volume= 3 |page= 32 |year= 1917 |publisher= McGraw-Hill }}</ref>

The most common W-type engine is the 4-bank type, with the [[Volkswagen Group]] experimenting with the [[Passat]] W8 and its 4.0 liter, 4-bank W8 engine and later implementing the concept with the group's [[Bentley]] division, creating a 6.0 liter [[W12 engine|W12]] in both naturally aspirated and [[turbocharged]] variants. Due to the pre-existing [[VR6 engine|VR-type engine]] only needing one cylinder head despite having two banks of cylinders, a Volkswagen 4-bank W-type engine is structured more similarly to a conventional 2-bank [[V engine]] as opposed to a "true" W engine.

W engines are significantly less common than V engines. Compared with a V engine, a W engine is typically shorter but wider. In Volkswagen’s case, this allows for superior packaging in engine compartments intended for 6 and 8 cylinder engines, the Passat W8 being one such example.