PSA PEUGEOT CITRO╦N is bringing out a new high-pressure
direct-injection petrol engine featuring lean-burn stratified-charge technology. It is the
first engine of this type to be developed by a European carmaker. The new engine HPi was
developed in-house by PSA PEUGEOT CITRO╦N over a period of 121 weeks with a total
investment budget of FF 420 million (64 million euro). It will be manufactured at the
TrÚmery engines plant in Frances Moselle region at a rate of 200 units per day. The
HPi engine will be fitted on upper-mid-range Peugeot and CitroŰn vehicles from the second
quarter of 2000.
The new HPi engine
has a capacity of two litres and develops an output power of 103 kW (143 bhp). Specific
advantages include the following:
is 19% lower than the previous-generation XU two-litre engine and 10% lower than the
recent EW two-litre indirect-injection engine (regulatory cycle). On an urban driving
cycle, the improvement is even more remarkable, with consumption 21% lower than the XU and
11% lower than the EW.
Engine response at
low running speed is improved, with torque of 170 Nm available at 2000 rpm, an improvement
of 9.6% on the XU engine and 3.6% on the EW. Environmental performance is improved
through a significant reduction in CO2 emissions, which is proportional to fuel
consumption. Emissions are well within the Euro 3 regulations (2001) and compatible with
the Euro 4 standards scheduled for 2005.
To achieve these
improvements, PSA PEUGEOT CITRO╦N designed the HPi engine using the most advanced
technology available today: lean-burn stratified-charge direct fuel injection.
technology involves concentrating an inflammable air/petrol mixture in the vicinity of the
spark plug, then filling the rest of the combustion chamber with air. Intake must be
closely matched to engine speed and requires precise fuel injection directly into the
developed the high-pressure petrol injection pump for the HPi engine through a joint
venture with Siemens. The pump supplies injection pressure of between 30 and 100 bars,
compared with 3.5 bars on a conventional petrol engine. The high injection pressure and
lean fuel mix that can be used with stratified charge, substantially reduce the amount of
fuel required for combustion, and so bring significant fuel savings.
Owing to the
excess air in the combustion mix, however, the exhaust gas contains far more oxygen than a
conventional engine. Special measures are therefore required to reduce emissions of
nitrogen oxides (NOx). To solve this problem, PSA PEUGEOT CITRO╦N has developed a
sequential NOx treatment system based on a storage-release principle.
The new HPi
direct-injection petrol engine marks the latest step in an ambitious engine development
policy initiated by PSA PEUGEOT CITRO╦N in 1998 with the HDi high-pressure common-rail