The straight-five engine (also referred to as an inline-five engine; abbreviated I5 or L5) is a piston engine with five cylinders mounted in a straight line along the crankshaft.
Although less common than straight-four engines and straight-six engines, straight-five engines have occasionally been used by automobile manufacturers since the late 1930s, particularly the Mercedes Benz's diesel engines from 1974 to 2006 and Audi's petrol engines from 1979 to the present. Straight-five engines are smoother running than straight-four engines and shorter than straight-six engines. However, achieving consistent fuelling across all cylinders was problematic prior to the adoption of fuel injection.
Five-cylinder engines have a crankshaft with 72 degree angles.[3] Amongst four-stroke engines, an advantage of engines with five or more cylinders is that the power strokes are overlapping (if the engine has an even firing order).[1]
On the other hand, the odd number of cylinders in a straight-five engine results in imperfect primary and secondary engine balance (unlike a straight-six engine). Counterweights on the crankshaft (also used in straight-four engines) can be used to reduce the vibrations from these imbalances.[4][5]
All two stroke straight-five engines are limited in having a single firing order for a given crank configuration; because a complete cycle occurs every 360 degrees, there is no chance to share piston phases without having simultaneous ignitions, so the straight-five is at no disadvantage in this case. Some two-stroke outboard engines, e.g. the Mercury Marine Force 150 engine use a firing order of 1-5-2-3-4.[8]
Carburettors and fuel injection
The use of straight-five petrol engines in mass production cars only became truly viable with the advent of reliable fuel injection. This is because of the unavoidable problems of a carburettor supplying an odd number of cylinders and the length of the inlet manifold between the carburetor varying greatly between cylinders at the ends of the engine and those nearer the carburetor. Unlike other engine layouts, these problems are not easily solved by using multiple carburettors.
Diesel engines have always used fuel injection, therefore large displacement straight-five diesel engines were commonly seen decades before straight-five petrol engines.
Usage in automobiles
Diesel engines
The 1938 Lancia 3Ro trucks introduced a straight-five diesel engine to replace the previous straight-three engine. Built for the Italian and German armed forces during World War II and later for civilian usage, the truck remained in production until 1950.[9]
The first mass-production straight-five passenger car engine was the 1974 Mercedes-Benz OM617, a naturally-aspirated 3.0 L (183 cu in) engine introduced in the Mercedes-Benz 300D (W114/W115) models. In 1978, a turbocharged version was introduced in the Mercedes-Benz 300SD Turbo models. Mercedes-Benz continued to produce straight-five engines for the next 28 years, until the Mercedes-Benz OM647 engine ended production in 2006.
In 1978, the Audi 2.0 R5 D engine was introduced in the Audi 100 sedan. In 1983, a turbocharged version was introduced, initially for the U.S market Audi 100. Several Volvo cars were produced with Audi straight-five diesel engines, prior to the introduction of the Volvo D5 turbo-diesel engine; this engine was produced from 2001 to 2017 and was used in several diesel hybrid applications (marketed as "twin engine" models).[10][11]
Other mass-production straight-five diesel engines include the 1999-2001 VM Motori 531 turbo-diesel engine,[12] the 1998-2007 Land Rover Td5 turbo-diesel engine, the 2006-2019 Ford Duratorq 3.2 turbo-diesel engine and the 1998-2009 Fiat JTD 2.4 turbo-diesel engine.
Henry Ford had an inline-five engine developed in the late 1930s to early 1940s for a compact economy car design, which never saw production due to lack of demand for small cars in the United States.[13]
The first production straight-five petrol engine was the Audi 2.1 R5 introduced in the Audi 100 in 1979. Audi has continued use of straight-five petrol engines (in both naturally aspirated and turbocharged versions) to the present day. The Audi TT RS and Audi RS3 currently use straight-five engines.[14] In motorsport, the first car to use a straight-five engine was the Audi Quattro rally car;[15] other racing cars which used straight-five engines include the 1985-1986 Audi Sport Quattro E2 and the 1989 Audi 90 Quattro IMSA GTO.[16][17][18][19] For the year 1987 factory team tested a 1000 hp version of the inline-5 powered Audi S1 Sport Quattro.[20]
Several Volkswagen-branded straight-five engines have been produced, beginning with the Volkswagen WH/WN 1.9 litre 10v engine used in the 1981 Volkswagen Passat. The final Volkswagen straight-five petrol engine was the Volkswagen EA855 2.5 litre 20v engine used in the North American Passat models until 2014.[21]
The Volvo Modular engine was introduced in the 1991 Volvo 850 sedan and was used in various Volvo models, along with the Ford Focus ST and Ford Focus RS models. All of the straight-five petrol engines used by Volvo and Ford were built at the Volvo Skövde engine plant in Skövde, Sweden, until their discontinuation in 2016.
Very few motorcycles have used five-cylinder engines. However, the 1965 Honda RC148 and 1966 Honda RC149 125 cc four-stroke racing motorcycles used straight-five engines based on the 50 cc straight-twin engine from the Honda RC116 Grand Prix racing motorcycle.[23][24] These straight-five engines were an unusual design in that they were configured as a straight-six engine with one of the middle cylinders removed.[25]
See also
Wikimedia Commons has media related to Straight-5 engines.
^"Audi 90 quattro IMSA-GTO". www.classicdriver.com.
^"Detailed specs review of 1989 Audi 90 Quattro IMSA-GTO model for North America racing/rallye". www.automobile-catalog.com.
^"ableitet.no - Audi 90 IMSA GTO". www.ableitet.no.
^"Retrospective>> Quattro Firepower: The Imsa Audi 90 Gto - Speedhunters". 26 May 2009.
^. Archived from the original on 2015-01-18. Retrieved 2015-01-16.
^"2014 Volkswagen Passat". www.cars.com. Retrieved 24 August 2022.
^Herriott, Richard (21 August 2014). "Theme – Engines: Throbby, Thrummy Quints". Driven To Write. from the original on 2022-06-25.
^"Honda's two-wheeled glory years". www.goodwood.com. Retrieved 23 August 2022.
^"The 1966 Honda RC149". Cycle News. Retrieved 23 August 2022.
^"RC 148 / RC149" (in Japanese). Retrieved 25 October 2019.
January 20, 2023
straight, five, engine, straight, five, engine, also, referred, inline, five, engine, abbreviated, piston, engine, with, five, cylinders, mounted, straight, line, along, crankshaft, although, less, common, than, straight, four, engines, straight, engines, stra. The straight five engine also referred to as an inline five engine abbreviated I5 or L5 is a piston engine with five cylinders mounted in a straight line along the crankshaft Although less common than straight four engines and straight six engines straight five engines have occasionally been used by automobile manufacturers since the late 1930s particularly the Mercedes Benz s diesel engines from 1974 to 2006 and Audi s petrol engines from 1979 to the present Straight five engines are smoother running than straight four engines and shorter than straight six engines However achieving consistent fuelling across all cylinders was problematic prior to the adoption of fuel injection Contents 1 Characteristics 1 1 Engine balance and vibration 1 2 Firing order 1 3 Carburettors and fuel injection 2 Usage in automobiles 2 1 Diesel engines 2 2 Petrol engines 3 Usage in motorcycles 4 See also 5 ReferencesCharacteristics Edit Animation of the 1 2 4 5 3 firing order MAN B amp W 5S50MC 1 865 litre marine diesel engine Straight five engines are typically shorter than straight six engines making them easier to fit transversely in an engine bay 1 They are also smoother than straight four engines 1 and are narrower than V engines 2 and flat engines Engine balance and vibration Edit Five cylinder engines have a crankshaft with 72 degree angles 3 Amongst four stroke engines an advantage of engines with five or more cylinders is that the power strokes are overlapping if the engine has an even firing order 1 On the other hand the odd number of cylinders in a straight five engine results in imperfect primary and secondary engine balance unlike a straight six engine Counterweights on the crankshaft also used in straight four engines can be used to reduce the vibrations from these imbalances 4 5 Firing order Edit Most four stroke straight five engines use a firing order of 1 2 4 5 3 6 This firing order results in the minimal primary crank speed rocking couple and is used by the Volvo Modular engine VW Audi straight five engine General Motors Atlas engine and Honda G engine Straight five engines typically have a 72 degree crankshaft design 7 All two stroke straight five engines are limited in having a single firing order for a given crank configuration because a complete cycle occurs every 360 degrees there is no chance to share piston phases without having simultaneous ignitions so the straight five is at no disadvantage in this case Some two stroke outboard engines e g the Mercury Marine Force 150 engine use a firing order of 1 5 2 3 4 8 Carburettors and fuel injection Edit The use of straight five petrol engines in mass production cars only became truly viable with the advent of reliable fuel injection This is because of the unavoidable problems of a carburettor supplying an odd number of cylinders and the length of the inlet manifold between the carburetor varying greatly between cylinders at the ends of the engine and those nearer the carburetor Unlike other engine layouts these problems are not easily solved by using multiple carburettors Diesel engines have always used fuel injection therefore large displacement straight five diesel engines were commonly seen decades before straight five petrol engines Usage in automobiles EditDiesel engines Edit The 1938 Lancia 3Ro trucks introduced a straight five diesel engine to replace the previous straight three engine Built for the Italian and German armed forces during World War II and later for civilian usage the truck remained in production until 1950 9 The first mass production straight five passenger car engine was the 1974 Mercedes Benz OM617 a naturally aspirated 3 0 L 183 cu in engine introduced in the Mercedes Benz 300D W114 W115 models In 1978 a turbocharged version was introduced in the Mercedes Benz 300SD Turbo models Mercedes Benz continued to produce straight five engines for the next 28 years until the Mercedes Benz OM647 engine ended production in 2006 In 1978 the Audi 2 0 R5 D engine was introduced in the Audi 100 sedan In 1983 a turbocharged version was introduced initially for the U S market Audi 100 Several Volvo cars were produced with Audi straight five diesel engines prior to the introduction of the Volvo D5 turbo diesel engine this engine was produced from 2001 to 2017 and was used in several diesel hybrid applications marketed as twin engine models 10 11 Other mass production straight five diesel engines include the 1999 2001 VM Motori 531 turbo diesel engine 12 the 1998 2007 Land Rover Td5 turbo diesel engine the 2006 2019 Ford Duratorq 3 2 turbo diesel engine and the 1998 2009 Fiat JTD 2 4 turbo diesel engine Petrol engines Edit An Audi 2 3 NG engine mounted longitudinally A Volvo B5244S engine mounted transversely Henry Ford had an inline five engine developed in the late 1930s to early 1940s for a compact economy car design which never saw production due to lack of demand for small cars in the United States 13 The first production straight five petrol engine was the Audi 2 1 R5 introduced in the Audi 100 in 1979 Audi has continued use of straight five petrol engines in both naturally aspirated and turbocharged versions to the present day The Audi TT RS and Audi RS3 currently use straight five engines 14 In motorsport the first car to use a straight five engine was the Audi Quattro rally car 15 other racing cars which used straight five engines include the 1985 1986 Audi Sport Quattro E2 and the 1989 Audi 90 Quattro IMSA GTO 16 17 18 19 For the year 1987 factory team tested a 1000 hp version of the inline 5 powered Audi S1 Sport Quattro 20 Several Volkswagen branded straight five engines have been produced beginning with the Volkswagen WH WN 1 9 litre 10v engine used in the 1981 Volkswagen Passat The final Volkswagen straight five petrol engine was the Volkswagen EA855 2 5 litre 20v engine used in the North American Passat models until 2014 21 The Volvo Modular engine was introduced in the 1991 Volvo 850 sedan and was used in various Volvo models along with the Ford Focus ST and Ford Focus RS models All of the straight five petrol engines used by Volvo and Ford were built at the Volvo Skovde engine plant in Skovde Sweden until their discontinuation in 2016 Other straight five petrol engines include 1989 1998 Honda G series 2 0 2 5 litre 20v engines 1995 2006 Fiat Family C 2 0 2 4 litre 20v engine 2004 2012 General Motors Vortec 3500 3700 3 5 3 7 litre 20v enginesIn recent years the engine has been falling out of favour with Volvo announcing in 2012 it would discontinue building them for example 22 Usage in motorcycles EditSee also List of motorcycles by type of engine Straight five Very few motorcycles have used five cylinder engines However the 1965 Honda RC148 and 1966 Honda RC149 125 cc four stroke racing motorcycles used straight five engines based on the 50 cc straight twin engine from the Honda RC116 Grand Prix racing motorcycle 23 24 These straight five engines were an unusual design in that they were configured as a straight six engine with one of the middle cylinders removed 25 See also Edit Wikimedia Commons has media related to Straight 5 engines Straight engine V5 engine VR5 engineReferences Edit a b c The Advantages And Disadvantages Of The Inline Five Cylinder Engine Car Throttle Retrieved 20 August 2022 Inline vs V Engine Why High End www whyhighend com Retrieved 20 August 2022 Gimme Five www hemmings com Retrieved 21 August 2022 Robert Bosch GmbH Bosch Automotive Handbook 6th edition p 459 463 Professional Engineering Publishing 2004 ISBN 1 86058 474 8 Bednar Fundamentals of Combustion 1989 Firing Order of Cylinders Automobile what when how com https www hemmings com blog article gimme five bare URL 150 H P 1989 1992 Force Outboard 1989 A THRU 1992 C CRANKSHAFT PISTON Diagram and Parts Archived from the original on 2015 12 08 Retrieved 2015 12 02 Storia Illustrata del Camion Italiano in Italian Edizione Neri ISBN 978 88 900 955 8 0 V60 GBen Ipaper ipapercms dk Retrieved 2018 05 17 History of the Volvo 5 Cylinder 11 October 2017 VM Motori 3 1 531 OHV engine AutoManiac Retrieved 24 August 2022 Henry Ford s Weird Old Engines Popular Science Bonnier Corporation p 195 August 1960 Sutton Mike 2017 10 16 400 HP 2017 Audi RS3 Tested Car and Driver Retrieved 2023 01 17 Graham Robson 2008 06 15 Audi Quattro p 12 ISBN 9781845841416 Audi 90 quattro IMSA GTO www classicdriver com Detailed specs review of 1989 Audi 90 Quattro IMSA GTO model for North America racing rallye www automobile catalog com ableitet no Audi 90 IMSA GTO www ableitet no Retrospective gt gt Quattro Firepower The Imsa Audi 90 Gto Speedhunters 26 May 2009 Secret Rally Car Audi Group S Prototype Archived from the original on 2015 01 18 Retrieved 2015 01 16 2014 Volkswagen Passat www cars com Retrieved 24 August 2022 Herriott Richard 21 August 2014 Theme Engines Throbby Thrummy Quints Driven To Write Archived from the original on 2022 06 25 Honda s two wheeled glory years www goodwood com Retrieved 23 August 2022 The 1966 Honda RC149 Cycle News Retrieved 23 August 2022 RC 148 RC149 in Japanese Retrieved 25 October 2019 Retrieved from https en wikipedia org w index php title Straight five engine amp oldid 1134232256, wikipedia, wiki, book, books, library,
