In internal combustion engines, a variable-length intake manifold (VLIM),variable intake manifold (VIM), or variable intake system (VIS) is an automobile internal combustion engine manifold technology. As the name implies, VLIM/VIM/VIS can vary the length of the intake tract in order to optimise power and torque across the range of engine speed operation, as well as to help provide better fuel efficiency. This effect is often achieved by having two separate intake ports, each controlled by a valve, that open two different manifolds – one with a short path that operates at full engine load, and another with a significantly longer path that operates at lower load. The first patent issued for a variable length intake manifold was published in 1958, US Patent US2835235 by Daimler Benz AG.[1]
Lower intake manifold on a 1999 Mazda Miata engine, showing components of a variable-length intake system.
There are two main effects of variable intake geometry:
Swirl
Variable geometry can create a beneficial air swirl pattern, or turbulence in the combustion chamber. The swirling helps distribute the fuel and form a homogeneous air-fuel mixture. This aids the initiation of the combustion process, helps minimise engine knocking, and helps facilitate complete combustion. At low revolutions per minute (rpm), the speed of the airflow is increased by directing the air through a longer path with limited capacity (i.e., cross-sectional area) and this assists in improving low engine speed torque. At high rpm, the shorter and larger path opens when the load increases, so that a greater amount of air with least resistance can enter the chamber. This helps maximise 'top-end' power. In double overhead camshaft (DOHC) designs, the air paths may sometimes be connected to separate intake valves[citation needed] so the shorter path can be excluded by de-activating the intake valve itself.
Pressurisation
A tuned intake path can have a light pressurising effect similar to a low-pressure supercharger due to Helmholtz resonance. However, this effect occurs only over a narrow engine speed band. A variable intake can create two or more pressurized "hot spots", increasing engine output. When the intake air speed is higher, the dynamic pressure pushing the air (and/or mixture) inside the engine is increased. The dynamic pressure is proportional to the square of the inlet air speed, so by making the passage narrower or longer the speed/dynamic pressure is increased.
Applications
Many automobile manufacturers use similar technology with different names. Another common term for this technology is variable resonance induction system (VRIS).
Acura — Variable Volume Induction 3.0-litre V6 C30A (1991-2005) and 3.2-litre V6 C32B (1997-2005); 3.2 L V6 J32A3 (2004-2008); 2.0-litre I4 R20A (2013-2015) petrol engines
Audi — 2.8-litre V6 petrol engine (1991–98); 3.0-litre V6 (2002-2005); 3.6 and 4.2-litre V8 engines, 1987–present
BMW — DISA (DIfferenzierte SaugAnlage – "Differential Air Intake"), two Port: M42, three Port: N52; DIVA (variable length runners): M54 etc. BMW's DIVA (Differentiated Variable Air Intake) used on the N62 V8 engine, is the world's first continuously variable length intake manifold.[2]
Citroën — XM 3,0 V6.24 (200 hp) used during 1991 to 1997, ZX Coupe 2.0 16v XU10J4 engine.
Daewoo — Variable Geometry Induction System (VGIS) Lanos
Dodge / Chrysler — 3.5 L V6 EGE, (1993-1997) used in Dodge Intrepid, Chrysler Concorde and LHS; 2.0 A588 - ECH (2001–2005) used in the 2001-2005 model year Dodge Neon R/T; 6.4 L V8 2011-2014 Dodge Charger and Challenger, Chrysler 300, Jeep Grand Cherokee (SRT8 versions)
Ford — Dual-Stage Intake (DSI), on their Duratec 2.5 and 3.0-litre V6s, and it was also found on the Yamaha V6 in the Taurus SHO. The Ford Modular V8 engines and the V6 Cologne use either the Intake Manifold Runner Control (IMRC) for four-valve engines, or the Charge Motion Control Valve (CMCV) for three-valve engines. The SVT edition (in North America) and ST170 edition (in Europe) of the Ford Focus added IMRC to the Ford Zetec engine. A system called Split Port Induction (SPI) was used on the 2.0L CVH I4 of the 1997-2002 Escort and 2000-2004 Focus, and the 3.8L Essex V6 of the 1996-2003 Windstar and 2001-2004 Mustang.
Volvo — V-VIS[5] (Volvo Variable Induction System) Volvo B52 engine as found on the Volvo 850. Longer inlet ducts used between 1,500 and 4,100 rpm at 80% load or higher.[6]
^Hirschfelder, Klaus; Völkl, Werner; Kühnel, Hans-Ulrich; Sinn, Walther; Huck, Armin (March 2002). "The first continuously variable intake system in the new eight-cylinder engine from BMW". MTZ Worldwide. 63 (3): 2–6. doi:10.1007/bf03227525. ISSN 2192-9114.
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This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Variable length intake manifold news newspapers books scholar JSTOR June 2009 Learn how and when to remove this template message In internal combustion engines a variable length intake manifold VLIM variable intake manifold VIM or variable intake system VIS is an automobile internal combustion engine manifold technology As the name implies VLIM VIM VIS can vary the length of the intake tract in order to optimise power and torque across the range of engine speed operation as well as to help provide better fuel efficiency This effect is often achieved by having two separate intake ports each controlled by a valve that open two different manifolds one with a short path that operates at full engine load and another with a significantly longer path that operates at lower load The first patent issued for a variable length intake manifold was published in 1958 US Patent US2835235 by Daimler Benz AG 1 Lower intake manifold on a 1999 Mazda Miata engine showing components of a variable length intake system There are two main effects of variable intake geometry Swirl Variable geometry can create a beneficial air swirl pattern or turbulence in the combustion chamber The swirling helps distribute the fuel and form a homogeneous air fuel mixture This aids the initiation of the combustion process helps minimise engine knocking and helps facilitate complete combustion At low revolutions per minute rpm the speed of the airflow is increased by directing the air through a longer path with limited capacity i e cross sectional area and this assists in improving low engine speed torque At high rpm the shorter and larger path opens when the load increases so that a greater amount of air with least resistance can enter the chamber This helps maximise top end power In double overhead camshaft DOHC designs the air paths may sometimes be connected to separate intake valves citation needed so the shorter path can be excluded by de activating the intake valve itself Pressurisation A tuned intake path can have a light pressurising effect similar to a low pressure supercharger due to Helmholtz resonance However this effect occurs only over a narrow engine speed band A variable intake can create two or more pressurized hot spots increasing engine output When the intake air speed is higher the dynamic pressure pushing the air and or mixture inside the engine is increased The dynamic pressure is proportional to the square of the inlet air speed so by making the passage narrower or longer the speed dynamic pressure is increased Applications EditMany automobile manufacturers use similar technology with different names Another common term for this technology is variable resonance induction system VRIS Acura Variable Volume Induction 3 0 litre V6 C30A 1991 2005 and 3 2 litre V6 C32B 1997 2005 3 2 L V6 J32A3 2004 2008 2 0 litre I4 R20A 2013 2015 petrol engines Audi 2 8 litre V6 petrol engine 1991 98 3 0 litre V6 2002 2005 3 6 and 4 2 litre V8 engines 1987 present Alfa Romeo Twin Spark 16v 1 8 and 2 0 litre and JTS engines BMW DISA DIfferenzierte SaugAnlage Differential Air Intake two Port M42 three Port N52 DIVA variable length runners M54 etc BMW s DIVA Differentiated Variable Air Intake used on the N62 V8 engine is the world s first continuously variable length intake manifold 2 Citroen XM 3 0 V6 24 200 hp used during 1991 to 1997 ZX Coupe 2 0 16v XU10J4 engine Daewoo Variable Geometry Induction System VGIS Lanos Dodge Chrysler 3 5 L V6 EGE 1993 1997 used in Dodge Intrepid Chrysler Concorde and LHS 2 0 A588 ECH 2001 2005 used in the 2001 2005 model year Dodge Neon R T 6 4 L V8 2011 2014 Dodge Charger and Challenger Chrysler 300 Jeep Grand Cherokee SRT8 versions Ferrari 360 Modena 550 Maranello LaFerrari Fiat Controlled High Turbulence 1989 92 Fiat Croma CHT StarJet engine dubbed Port Deactivation PDA Variable Intake System on the 131HP 1 8 16V and on the 155 HP 2 0 20V Pratola Serra engine Ford Dual Stage Intake DSI on their Duratec 2 5 and 3 0 litre V6s and it was also found on the Yamaha V6 in the Taurus SHO The Ford Modular V8 engines and the V6 Cologne use either the Intake Manifold Runner Control IMRC for four valve engines or the Charge Motion Control Valve CMCV for three valve engines The SVT edition in North America and ST170 edition in Europe of the Ford Focus added IMRC to the Ford Zetec engine A system called Split Port Induction SPI was used on the 2 0L CVH I4 of the 1997 2002 Escort and 2000 2004 Focus and the 3 8L Essex V6 of the 1996 2003 Windstar and 2001 2004 Mustang General Motors 3 9 litre LZ8 LZ9 V6 3 2 litre LA3 V6 LT5 5 7 litre GM Korea DOHC versions of E TEC II engines Holden Alloytec Honda Integra Legend NSX Prelude Civic Accord Hybrid Ridgeline Honda Civic ninth generation Hyundai XG V6 Isuzu Rodeo used in the second generation V6 3 2 litre 6VD1 Rodeos and third generation Gemini 1 6 litre 16v 4XE1 engines Jaguar AJ V6 Kia Carnival Sedona Land Rover Variable Geometry Induction Freelander V6 2001 2006 Lancia VIS Mazda Variable Inertia Charging System VICS is used on the Mazda FE DOHC engine and Mazda B engine family of inline four engines and Variable Resonance Induction System VRIS in the Mazda K engine family of V6 engines An updated version of this technology is employed on Mazda s new Z and L engines which is also used by Ford as the Duratec Mercedes Benz V6 M112 V6 M272 V8 AMG M156 MG ZT 190 180 160 2001 2005 ZS 180 2001 2005 Mitsubishi Mitsubishi Variable Induction Management MVIM 1991 1999 3000GT NA DOHC 2003 2005 Eclipse Nissan inline four engines V6 engines V8 engines Opel TWINPORT modern versions of Ecotec Family 1 and Ecotec Family 0 inline four engines and inline three engines a similar technology is used in 3 2 litre 54 V6 engine Peugeot 2 2 litre inline four engine 3 0 litre V6 2 0 16v XU10J4 engine non z version Porsche 928 flappy 3 4 VarioRam 964 993 996 Boxster Proton Campro CPS and VIM Proton Gen 2 CPS and Proton Waja CPS Proton Campro IAFM 2008 Proton Saga 1 3 Renault Clio 2 0 RS Roewe Variable Geometry Induction Roewe 750 2 5 2006 present Rover Variable Geometry Induction Rover 825 1996 1999 Rover 75 V6 1998 2005 Subaru Subaru Legacy Japan only using EJ204 version D 2 0 Litre Naturally aspirated engine Suzuki VIS Toyota Toyota Variable Induction System T VIS used in the early versions of the 1G GEU 3S GTE 3S GE and 4A GE families and Acoustic Control Induction System ACIS used in E G GR GZ JZ M S MZ UR UZ and VZ engine families Volkswagen 1 6 litre inline four engine V6 engines VR5 engines VR6 engines W8 engines V8 engines Volvo V VIS 5 Volvo Variable Induction System Volvo B52 engine as found on the Volvo 850 Longer inlet ducts used between 1 500 and 4 100 rpm at 80 load or higher 6 References Edit US Patent 2835235 Hirschfelder Klaus Volkl Werner Kuhnel Hans Ulrich Sinn Walther Huck Armin March 2002 The first continuously variable intake system in the new eight cylinder engine from BMW MTZ Worldwide 63 3 2 6 doi 10 1007 bf03227525 ISSN 2192 9114 928 Tech Tips Tip 78 90 GT Flapectomy Modified VVIS control PDF www paerl it 2011 12 11 Archived PDF from the original on 2017 07 11 Retrieved 2017 12 21 Volvo Car Corporation EngineTechInfo PDF Retrieved 2017 12 21 a href Template Cite web html title Template Cite web cite web a CS1 maint url status link Retrieved from https en wikipedia org w index php title Variable length intake manifold amp oldid 1150228018, wikipedia, wiki, book, books, library,
