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Orbital Achieves Breakthrough Emissions Capability On 4 Stroke Engine

5 October 1999

Orbital Achieves Breakthrough Automotive Emissions Capability On 4 Stroke Engine

    PERTH, Australia, Oct. 4 -- Orbital Engine Corporation's
direct fuel injection system has achieved a new benchmark
for emissions reduction and fuel economy in the automotive industry.  In tests
conducted by RWTUV Fahrzeug GmbH, the technical body responsible for exhaust
emissions in Germany, an Orbital vehicle has achieved vehicle emissions levels
within the European Stage 4 emissions limits for the year 2005.  Importantly,
these results were achieved without a lean NOx catalyst.  Using Orbital's air
assisted direct injection the four cylinder, four stroke test vehicle also
achieved a 10% improvement in fuel economy over an identical vehicle fitted
with multi-point injection.
    "This achievement demonstrates that expensive additional or new technology
catalysts would not be essential to control NOx emissions in order to allow
lean burn stratified charge direct fuel injection engines to meet the
legislated requirements of the new millennium," said Mr. Kim Schlunke, Orbital
CEO.  He added, "Alternative stratified charge direct injection systems
typically increase the fundamental engine emission levels in order to achieve
a fuel economy advantage, which is less than that achieved by the Orbital
system."
    This new generation of the Orbital Combustion Process (OCP) gasoline
direct injection technology allows engines to operate on available European
gasoline fuels whose sulphur levels are too high for the new technology lean
NOx catalyst.
    "With this independent verification we believe we have successfully
demonstrated that Orbital's direct injection technology, when applied to
conventional four stroke automotive engines, can meet the dual demands of the
European automotive market for fuel economy and low cost emissions control.
OCP allows manufacturers to minimize the technology and cost associated with
converting their engines systems to achieve the fuel economy advantages
provided by direct injection.  The reduced cost and risk should therefore
improve the opportunity for penetration of this technology across the vehicle
fleet.  The opportunity to realize a substantial margin over the new current
Euro 3 standards, in combination with the tax incentivised reduced levels,
with a conventional catalyst also represents an exciting near term commercial
opportunity for many vehicle manufacturers," said Schlunke.
    The testing was conducted by RWTUV Fahrzeug GmbH, the technical body
responsible for exhaust emissions in Germany, on a European sedan powered by a
2.0 litre DOHC four-stroke engine.  Fitted with OCP fuel system technology and
a conventional three-way catalyst the vehicle achieved significant margins
over the emissions levels of the European standard.  The test results, shown
below, were achieved over the European Stage 4 drive cycle (MVEG-B) and verify
results already achieved at Orbital's testing facilities in Western Australia.

                            Independently Measured
                         Orbital DI Vehicle Emissions

             MVEG-B Drive Cycle, New Underbody Three Way Catalyst
       1360kg, 2 l 4-V engine, JM370 catalyst, measured by RWTUV, Essen

    Hydrocarbons (g/km)
    EURO 3     0.20
    EURO 4     0.10
    OCP DI     0.063

    Oxides of Nitrogen (g/km)
    EURO 3     0.1
    EURO 4     0.0
    OCP DI     0.046

    Carbon Monoxide (g/km)
    EURO 3     2.30
    EURO 4     1.0
    OCP DI     0.35

    Euro 3 emission standards take effect in 2000, while the Euro 4 levels are
scheduled to take effect in 2005.  They will apply to all vehicles produced
and sold in Europe from those dates.  Within the automotive industry, the Euro
4 regulations are generally regarded as comparable to California's stringent
ULEV standards.
    The application of Orbital's direct injection technology to four-stroke
engines has been developed over a period of several years.  Orbital has been
working with a number of strategic partners to industrialize its technology,
including Siemens, Synerject, Johnson Matthey, Wabco and Champion.
    Orbital is a leading international developer of engine technologies using
direct in-cylinder fuel injection and lean-burn systems for enhanced fuel
economy and lower emissions.  The company serves the worldwide automotive,
marine, recreational and motorcycle markets.
    Mercury Marine, the world's leading producer of outboard engines, and
Bombardier, the market leader in personal watercraft, have both introduced
product using OCP technology which can meet marine emissions legislated for
the year 2006.  These levels represent a 75% reduction over 1998 levels.
    A major step in commercializing Orbital's technology also occurred
recently when Aprilia World Service B.V., Europe's second largest and fastest
growing motorcycle and scooter manufacturer, signed a license agreement with
Orbital as a precursor to volume production.
    Headquartered in Perth, Western Australia, Orbital stock is traded on the
Australian Stock Exchange (OEC), the New York Stock Exchange (OE) as well as
the Berlin (ORE) and Frankfurt (OREA) Exchanges.