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Press Release

Mitsubishi's GDI Engine


Mitsubishi Motors makes stellar leap in automotive technology with GDI

Performance, While Increasing Fuel Efficiency by up to 40%

Plans to Develop U.S. Version of Revolutionary Engine by Year 2000

Mitsubishi Motors America Inc., a subsidiary of Mitsubishi Motors
Corp. in Japan, held a briefing this week on one of the latest
innovations in the global automotive industry and gasoline engine
technology -- the Mitsubishi Motors In-Cylinder Direct Injection
Gasoline (GDI) engine.

The company said the new engine, which is in mass production and
currently being installed on several of its new cars, has been
critically acclaimed and has earned several prestigious international
awards for its ability to deliver significant improvements in fuel
economy and emissions without sacrificing power.

At the briefing, Dr. Hiromitsu Ando, Deputy General Manager of the
Engine Research Department at Mitsubishi Motors Corp., one of the main
developers of the GDI engine said, "the Mitsubishi Motors in-line,
four cylinder 1,834 c.c. GDI is an engine engineers dream. It features
10% more output and torque, faster acceleration, and 35-40% better
fuel efficiency during idling and varying speed conditions, compared
to conventional MPI engines. In addition, we have been able to control
NOx emissions, even while burning a lean fuel-air mixture."

The GDI engine is expected to become the cornerstone for the next
generation of high efficiency engines and will provide Mitsubishi
Motors with a competitive advantage in the global
marketplace. Considered the most significant engine technology
breakthrough since fuel injection engines 20 years ago, the GDI engine
is featured on the new Mitsubishi Motors Galant and Legnum station
wagon in Japan. The Mitsubishi Carisma, produced by NedCar in Europe,
will also feature the GDI engine later this year.  Since September
1996, more than 37,000 vehicles with the GDI engine have been
sold. According to Dr. Ando, Mitsubishi Motors plans to develop a
U.S. version of the GDI engine by year 2000.

Automotive engineers have believed for years that a GDI engine design
has the greatest potential for delivering the best performance and
lowest fuel consumption. In independent driving tests in Japan, the
mid-size 1997 Mitsubishi Galant Sedan with a GDI engine was driven up
to 800 miles on one tank of gas (17 gallons) achieving up to 47 miles
per gallon (approximately the distance from Detroit to Atlanta without
refueling). The GDI engine uses straight upright intake ports, instead
of horizontal intake ports found in conventional engines. The upright
straight intake ports generate an intense airflow pattern down against
curved-top pistons, which then redirect the airflow into a strong
reverse tumble for optimal fuel injection. Then, newly developed
high-pressure, electromagnetic swirl injectors spray atomized fuel
directly into the cylinder into the airflow just before
ignition. Before the atomized fuel spray disperses, it vaporizes above
the curved-top piston heads and is carried toward the spark plugs in
an optimally stratified form. Test results show that the richest
mixture of the stratified air-fuel charge concentrates around the
spark plugs just prior to ignition, contributing to the ultra-lean
fuel-air ratio. In comparison, conventional multi-port injection (MPI)
engines mix air and fuel together before injecting them into the
intake port of each cylinder.

Fuel consumption tests conducted at varying speeds and driving
conditions indicate the new Mitsubishi Motors engine uses 35% to 40%
less fuel than a conventional MPI engine. The most dramatic effect is
at idling speeds, where the new GDI engine's ability to maintain
stable combustion offers greater flexibility in setting the idle
speed. At 600 rpm, the ultra-lean combustion GDI engine with 40 to 1
air-fuel ratio consumes 40% less fuel than a conventional 14.7 to 1
MPI engine, which idles at about 750 rpm. At a running speed of 40
km/h (about 25 miles/h), the new Mitsubishi Motors engine burns 35%
less fuel than a comparably sized conventional engine. In gas-guzzling
city driving, the GDI engine consumes 35% less fuel than a
conventional engine and even outperforms diesel engines.

The outstanding fuel economy of the GDI engine does not adversely
affect its power; in fact, it enhances it.  Smoother air intake and
vaporization of fuel at a late stage of the compression stroke cools
the air for better volumetric efficiency and minimizes engine
knocking.  Another benefit of the new Mitsubishi Motors' engine design
is that it provides about 10% greater output and torque at all speeds,
compared with conventional MPI engines, and 5% greater acceleration,
whether used with manual or automatic transmissions.

The Mitsubishi Motors GDI engine also features two combustion modes
for maximum flexibility of operation.  Under most normal driving
conditions, at speeds of up to 120 km/h (about 72 miles/h), the engine
operates in the ultra-lean combustion mode in which fuel injection
occurs at the latter stage of the compression stroke and ignition
takes place at an air-fuel ratio of 1:30 to about 40. At higher
speeds, the engine switches to a high-output mode in which fuel
injection takes place during the intake stroke. In this mode,
combustion is optimized by ensuring a homogeneous, cooler air-fuel
mixture that minimizes the possibility of engine knocking.

Previous efforts to burn a lean air-fuel mixture have resulted in
difficulty to control NOx emission. However, in the case of GDI
engine, significant NOx reduction is achieved by utilizing high-rate
EGR (Exhaust Gas Ratio) such as 30% that is allowed by the stable
combustion unique to the GDI as well as a use of a newly developed
lean-NOx catalyst.

Established in 1973, Mitsubishi Motors America Inc. is headquartered
in Southfield, Mi. and monitors the technical, quality, warranty,
purchasing, and marketing areas of the U.S. automotive industry.

10/18/95 Design and Technology Award - Most Promising Technology Category; presented by CAR (U.K. automotive magazine) 2/7/96 Energy-Saving Vanguard - Ministry of International Trade and Industry Award; presented by Energy-Saving Center Foundation 4/5/96 Nikkei BP Technology Award, Machine Material category; presented by Nikkei BP (magazine) 12/19/96 96-97 RJR Technology of the Year Award; presented by RJC (Japan Automotive Research and Journalist Committee) 1/30/97 Top Ten New Products of 1996 Award; presented by Nikkan Shinbun (Industrial Daily Newspaper) 2/3/97 1996 Nihon Keizai Shinbun - Outstanding Product/Service Award; presented by Nihon Keizai Shinbun (Japan Economy Newspaper) 2/5/97 Paul Pietsch Award; presented by Auto Motor & Sport (German Automotive Magazine) 2/26/97 Most Outstanding Hi-Tech Award; presented by Sports Nippon Newspaper AWARDS RECEIVED BY MITSUBISHI MOTORS GALANT AND LEGNUM EQUIPPED WITH GDI ENGINE 11/18/96 Grand Champion Award; presented by Apollo Press (automotive magazine) 11/28/96 Car of the Year Award; presented by Japan Car of the Year Executive Committee 12/19/96 Outstanding Automobile Award; presented by RJC (Japan Automotive Researchers and Journalist Committee) 1/9/97 Gekkan Jidosha Award - Most Popular Domestic Passenger Car (monthly automobile magazine); presented by Naigai Press (publishing company) 1/14/97 1996 The Internet Car of the Year - Passenger Car Award; presented by Four By Four Magazine 1/18/97 Car Design Award-Golden Key Trophy; presented by Car Styling Press (automotive magazine) CONTACT: Scott Tangney | LobsenzStevens Inc. for | Mitsubishi Motors America, Inc. | 212/684-6300, ext. 313