Efficient, economical engines
HDi diesel engines
Citroën’s
HDi diesel engines have set the standard in terms of
comfort and
environmental impact. The C4 range now offers the
biggest-ever
selection of Airdream® engines. The Airdream®
eco-signature covers the
1.6-litre versions (HDi 92, HDi 110 DPFS with a manual
gearbox and
EGS6) and 2-litre versions with a manual gearbox.
The
2-litre HDi unit, coupled with a six-speed manual
gearbox, has been
upgraded to comply with the future Euro V standard.
Fitted as standard
with a particulate filter, the new HDi 140 DPFS, is
flexible, dynamic
and low on emissions. It now develops 103 kW of power
(140 bhp EEC).
Fuel consumption has been homologated at 5.3 l/100 km,
over a combined
cycle, while CO2 emissions are down to just 140 g/km.
The other diesel units – the HDi 92 (with or without
DPFS) and HDi 110 DPFS – are as dynamic as before, and
even cleaner.
These improvements result from the switch to low-rolling
resistance
Michelin Energy Saver® tyres, available on 16-inch
wheels.
Citroën has reduced the fuel consumption of both the HDi
92 and HDi 110
DPFS powerplants, to 4.4 l/100 km for the HDi 92, 4.4
l/100 km for the
HDi 110 DPFS manual and 4.4 l/100 km for the HDi 110
DPFS EGS6 over a
combined cycle, on the versions fitted with these tyres.
CO2 emissions
have been cut to 117 g/km, 119 g/km and 118 g/km,
respectively.
New petrol engines
The
C4 is now available with two petrol engines from the EP
family
co-developed with the BMW Group. It is the first Citroën
to be fitted
with engines from this family, namely the VTi 120,
replacing the 1.6i
16V, and the THP 150, replacing the 2.0i 16V.
The VTi
120 and THP 150 provide a perfect blend of performance,
driving
pleasure and fuel economy, with significantly lower
consumption and CO2
emissions.
?C4 VTi 120: dynamic and economical
Mainly through better management of intake, the VTi 120
engine offers
higher performance and therefore combines more power
with low fuel
consumption and lower CO2 emissions.
The
C4’s VTi 120 engine has a capacity of 1,598 cm3 and
develops 88 kW EEC
(120 bhp EEC) at a speed of 6,000 rpm, for maximum
torque of 160 Nm at
4,250 rpm.
These characteristics make the car much more pleasurable
to drive, with plenty of torque always on hand: 90% or
more of maximum
torque is available between 2,500 rpm and 5,750 rpm.
Mated
to a five-speed manual gearbox, the engine returns 6.7
l/100 km (159
g/km of CO2) over a combined cycle, down 6% on the old
unit.
The C4 VTi 120 therefore scores a neutral rating in
France’s new emissions bonus/surcharge system.
The VTi 120 unit also ships with a four-speed automatic,
for fuel
consumption of 7 l/100 km and CO2 emissions of 165 g/km.
VTi
stands for “Variable valve lift and Timing Injection”.
Fitted with an
aluminium block and cylinder head, the 16 valves are
driven by intake
and exhaust camshafts with continuously variable valve
timing.
The
intake valves also benefit from a variable raising
system that allows
the valves’ maximum travel to be adjusted gradually
depending on the
force applied to the accelerator pedal.
These two features boost engine efficiency, increasing
the
responsiveness of the vehicle through higher available
torque,
especially in the most frequent driving conditions (part
loads).
C4 THP 150: an outstanding combination of high
performance and low fuel consumption and emissions
With direct petrol injection and a turbocharger, the new
THP 150 offers both high performance and low
consumption.
The new unit develops maximum power of 110 kW (150 bhp
EEC) at 5,800
rpm, for maximum torque of 240 Nm from 1,400 rpm to
4,000 rpm. These
figures ensure driving pleasure akin to that provided by
the HDi diesel
units at low and medium engine speeds, with 156 Nm of
torque available
from as low as 1,000 rpm.
Mated
to the new MCM six-speed gearbox (with the same
architecture as the
EGS6), fuel consumption over a combined cycle is 6.9
l/100 km (for 164
g/km of CO2), down a full 10% on the previous engine.
The
C4 is also available with a four-speed automatic
gearbox, for maximum
power of 103 kW (140 bhp EEC). Maximum torque remains
the same, at 240
Nm at 1,400 rpm. Combined-cycle fuel consumption is 7.7
l/100 km, down
5% compared with the previous powerplant.
The THP 150 engine and the THP 140 version use the same
architecture as the VTi 120.
The unit features several technical particularities that
give it
outstanding performance for an engine of its size.
Comparable to the
downsizing applied to the Marque’s HDi engines, the
technology used for
the THP 150 unit brings significant gains over
normally-aspirated
engines.
Two of these technologies are completely new to the C4
range: direct petrol injection and the use of a
turbocharger.
The
THP engine (for Turbo High Pressure) features direct
sequential
injection fed by a high-pressure electronic pump. Linked
to a
turbocharger, the system has an intake camshaft with
continuous
variable timing.
The main characteristics of the engine are as follows:
-
Direct injection, which combines specific high power
with low fuel
consumption. This high pressure is obtained via a pump
mounted at the
end of the intake camshaft. Maximum pressure of 120 bars
allows the
injectors to spray the mixture directly into the
combustion chamber
sideways, ensuring uniform distribution. The compression
ratio is 10.5
to 1.
- A twin-scroll turbocharger. The particularity
of this system is that it groups the gas ducts by pair
(cylinders 1-4
and 2-3) in the exhaust manifold. The optimal gas flow
combination this
provides makes the turbine extremely fast-acting and
considerably cuts
down on lag time. The turbine can rotate at up to
200,000 rpm,
developing pressure limited electronically by the
discharge valve to
0.8 bars. Turbocharging is noticeable from 1,000 rpm.
-
A cylinder head with two overhead camshafts. The intake
camshaft
benefits from continuous variable timing, which provides
more torque at
low engine speeds while reducing fuel consumption and
CO2 emissions.
-
An oil pump with throughput regulation, which supplies
the right amount
of lubrication for optimal functioning and reduces fuel
consumption by
1%. This system also features an oil intercooler, fitted
in the filter
and regulated by a thermostat, for faster heating and
excellent
temperature management, even during rough handling.
- A
crankcase in two parts, with a cylinder casing and a
bearing cap
casing, in aluminium, for extra stiffness and reduced
noise emissions.
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