Mitsubishi 4A9 Engine

The Mitsubishi 4A9 engine is the newest family range of all-alloy inline four-cylinder engines from Mitsubishi Motors supermini, and built by DaimlerChrysler-owned MDC Power in Germany (previously a joint venture)."Newly Developed Compact, Aluminum Gasoline Engine"
, Mitsubishi Motors technical review

The engine project was begun as a joint effort by Mitsubishi Motors and DaimlerChrysler (DCX), with Mitsubishi handling the development of the engines and MDC Power GmbH, a company previously jointly established by Mitsubishi and DCX, handling production. The 4A9 is Mitsubishi's first four-cylinder engine family to adopt a high-pressure die-cast aluminum block."Colt Plus gets MDC Power"
Jack Yamaguchi, ''SAE International''

All engines developed within this family have aluminum cylinder block and head, four valves per cylinder, double overhead camshaft layouts, and ''MIVEC'' continuous variable valve timing (intake only).

Engine family characteristics

For high output and low fuel consumption, the MIVEC system and other measures (including optimized shaping of the intake and exhaust manifolds and cylinder head) were used to promote intake and exhaust efficiency. Optimally shaped cooling passages in the cylinder head and optimal control of the flow of coolant into the cylinder head help to suppress engine knocking. Comprehensive measures to engine components were taken to minimize friction.

For lightness and compactness; design optimization, material optimization, and component integration were identified as effective means of minimizing weight and bulk, so they were comprehensively effected in combination with each other. With regard to materials, the cylinder block is made of aluminum; the cylinder-head cover and intake manifold are made of plastic; the exhaust manifold has a pipe-based structure and cams driven by a timing chain. Component integration was applied in many areas of the engine. Notably, the functions of engine accessories were integrated into the cylinder block.

Exhaust emissions from the engine are minimized by measures including optimal design of the combustion chambers, optimal control of the intake air motion by means of the cylinder-head ports, employment of the MIVEC system, employment of an ultra-thin cylinder head gasket, and employment of micro-droplet fuel injectors. The vehicle's overall exhaust emissions are further suppressed by location of the exhaust manifold at the rear of the engine. This layout is beneficial since it minimizes the heat capacity of the exhaust system upstream of the catalytic converter and thus, together with combustion control, promotes activation of the catalytic converter.

4A91's DOHC camshafts are driven by a single-stage roller chain of pitch and width, instead of the previous 4G15's cogged belt drive. Camshafts act directly on bucket-type tappets. The intake camshaft is fitted with a continuously variable cam-phasing, altering timing up to 50 degrees. Valves are inclined at an included angle of 34 degrees versus the 4G15's wider 45 degrees.

4A90

Specifications

''Engine type'' — DOHC 16v, ECI multiple

''Displacement'' —

''Bore pitch'' —

''Bore'' —

''Stroke'' —

''Compression ratio'' — 10.5:1

''Power'' — at 6000 rpm

''Torque'' — at 4000 rpm

Applications

*2004-2012 Mitsubishi Colt
*2004–2006 Smart Forfour
*2011 Haima 2
*2014 BAIC Up
*2016 DFM Joyear X3
*Zotye Z200

4A91

Specifications

''Engine type'' — DOHC 16v, ECI multiple

''Displacement'' —

''Bore pitch'' —

''Bore'' —

''Stroke'' —

''Compression ratio'' — 10.5:1

''Power'' — at 6000 rpm

''Torque'' — at 4000 rpm

Applications

*2004 Mitsubishi Colt
*2007 Mitsubishi Lancer
*2004–2006 Smart Forfour
*2009–2019 Soueast V3
*2010 Brilliance FSV
*2011 Haima 2
*2012 Senova D20
*2013–present Soueast V5
*2013–present Zotye Z300
*2014 Senova D50
*2014–present Zotye SR7
*2016–2020 BAIC BJ20
*2016–present Ario S300
*2016 Brilliance V5
*2016 Senova X55
*2016 Yema T70 SUV
*2017 Soueast DX3
*Zotye Z200
*2017–present Soueast DX7
*2017–present Mitsubishi Xpander
*2019–present Nissan Livina

4A92

Specifications

''Engine type'' — DOHC 16v,ECI multiple

''Displacement'' —

''Bore pitch'' —

''Bore'' —

''Stroke'' —

''Compression ratio'' — 11.0:1

''Power'' — at 6000 rpm

''Torque'' — at 4000 rpm

Applications

*2010 Mitsubishi ASX (EU)
* 2011 Mitsubishi Lancer (EU)
* 2013 Mitsubishi Lancer (PH)
* 2011 Brilliance H530
* 2012 Brilliance V5
* 2012 Zotye Z300 (1.5/1.6L)
*2017/2018 DFM Joyear X3

See also

* List of Mitsubishi engines

References

External links

*

{{Mitsubishi Motors technologies

4A9
Straight-four engines
Gasoline engines by model