Please note: this is a work of fiction...
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By Jean Savary – translated by Julian Marsh
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Could
this be the first offspring of the PSA-Honda marriage? Citroên finally
seems to have come to terms with its past with the astonishing D5
revealed at the Mondial de l’Automobile. Beneath its self-evident
nostalgic styling, the D5 attempts to reinvent the automobile in much
the way its ancestor did in 1955. Indeed early examples of its
ancestor have recently been officially classified as part of France’s
national heritage.
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With
the launch of the D5 at the 2012 Mondial, Citroên is truly enjoying a
cultural revolution. Notwithstanding the disavowal of the
dieresis in the founder’s name with its recent replacement by a
circumflex (single chevron) accent, Citroên seems ready at last to
acknowledge its troubled past. And this new model represents a
rebirth. Not for them a mere styling revival like that of the
Mini 1 and 2 or certain Jaguars. This car resembles far more
closely the remarkable reinvention by Fiat of the 500 and X1/9 or that
of Saab with the 99 of 2010. Citroên timidly went there with the C3
which, if one squinted sufficiently hard, vaguely resembled the 2CV;
the C4 which had a slight taste of GS about it; the C6 which hovered
midway between SM and CX and let us not forget the C11 SUV with its
trapezoidal grille which recalled the H Van.
The D5
which replaces both the C6 and C5 is not evocative like these models
but represents a resurrection, reinventing as it does the DS which went
out of production all of 38 years ago. Its name inaugurates the
use of the letter D, lifted from its predecessor while the letter S has
become the number 5. Accusations of mere nostalgia are overcome
since with this new car, Citroên has renewed another of its traditions
– that of technical innovation. For the D5, it was not enough to
follow Peugeot one year later with a Valeo gadget, nor to launch an
“Evergreen” limited edition of the ageing C6 replete with Karaoke but
to radically rethink the architecture, the mechanics and the
interior.
Underneath a beautiful retro dress
designed by the new head of Style Citroên, Julien Jodry, the D5 is
radically innovative. With its rear engine and transmission; its
double glazed windscreen; its domino layout seating for five; its 100%
pneumatic suspension; and its safety innovations, the D5 recreated in
the Grand Hall of the Mondial the feverish scenes that occurred at a
certain Salon in 1955. It overshadowed the C5 which has remained
in production since 2008.
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A rear wheel drive Citroên
With
the mandatory fitting of antiskid technology (ESP) with effect from
2007, the conventional front engine layout is no longer viable.
The stability of a car is controlled electronically rather than being
due to the weight distribution. Furthermore, a front engine
represents a major problem in the event of a collision and requires
lengthy and heavy (and costly) frontal extensions to prevent the engine
from entering the passenger compartment. But this is not an “all
at the rear” design like the 1939 Beetle or the small Renaults of the
mid twentieth century; the D5’s transverse flat engine is placed
forward of the transmission in the manner of the Porsche Boxster.
Another innovation is its mounting in a toboggan which allows it to
move forwards and downwards in the event of a collision, thereby
reducing the inertia in much the same way as that of the Smart.
The weight of the new continuous variation belt drive transmission,
located between the driven wheels, is greatly reduced compared to that
of a conventional transmission. Despite the fact that Mercedes,
long wedded to rear wheel drive, is converting little by little to
front wheel drive (Class D and F), the use of rear wheel drive by the
major proponent of front wheel drive comes as a surprise.
Nevertheless, it is totally logical. In addition to the
improvements in passive safety and habitability that this layout
confers, there are benefits in braking thanks to the transfer of
inertia to the front wheels as attested by many generations of
Porsches. There are also benefits in grip.
Thus,
placed very low, the engine and transmission help reduce body roll and
also help maintain a very low body weight, not just at the front but in
its entirety. The bodyshell’s rigidity can be reduced since the
engine and transmission provide much of the necessary structural
rigidity. Two long lateral aluminium “caissons” provide the
requisite rigidity. Citroên claim that access to the mechanical bits is
very easy when the car is placed on a hydraulic lift and there is a
100,000 km (62,000 mile) service interval for the HCDI engine.
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A family of modular engines
Let
us refute the rumours of a six cylinder engine. The French
government ministry responsible for purchasing official cars has
rejected all but the three cylinder hybrid HCDI versions. Just
like the DS, the D5 must forget its dreams of mechanical grandeur in
the engine department but unlike its predecessor which laboured with
the ancient Traction engine, the D5 will not use the antiquated engines
that powered the C5 and C6. Instead, a new range of dry sump
engines, necessitated by its flat location has been
developed. In order to limit development costs,
Citroên has developed a family of modular diesel engines with three,
four or five cylinders, all of which share common components. The
three HCDI and the diesel/LPG (GNV) derivatives all have unique
crankshafts and blocks but otherwise employ identical components
although the peripheries obviously differ according to the
engine. Other innovations include piezo-electric valves from the
Peugeot Formula 1 engines and the replacement of the turbocharger by a
revolutionary helicoidal compressor (hélicoîdal according to
Citroên). The three diesels are respectively 1200cc, 1600cc and
2000cc developing 80, 100 and 120 kW respectively and offering typical
fuel consumption of 4, 4.8 and 5.5 litres per 100 km. The very
low weight of the D5 (1100 kg) and excellent aerodynamics explain this
sobriety.
In this connection, D5 benefits
from vents that evacuate hot air from the engine and also act as
spoilers to improve the aerodynamics unlike the DS. At speeds
above 80 kph (50 mph), a plate slides closed in the manner of the
air-brake of the Torpedo 909. The radiators are mounted laterally,
behind the swivelling wings (those of the DS had to be removed to
change a wheel), and are fed fresh air through the grill via side
conduits and by two conduits arranged in the floor. As for the petrol
versions, Honda retains exclusivity within the alliance but not having
any flat engine available, they will eventually be replaced by versions
of the four and five cylinders HCDI converted to GNV. Considering the
low projected sales, Citroên does not seem to be particularly concerned
and suggests that the new engines will be available at the end of 2013.
Patience will be rewarded because they will generate 130 kw and 170 kw
and record breaking consumption. Oh what fun one will be able to have
on the No Limit motorways run by the Cofiroad and Britasf
networks!
A double windscreen for silence
The lack of a front engine ensures a great reduction in noise and
vibrations and the double-glazed windscreen further reduces wind noise.
Not a traditional double glazing set up but two windscreens, 2 cm
apart, evoking the double rear window of the XM. The external screen
being a conventional one made out of polarizing and athermic laminated
glass, while the interior one being made out of anti-reflecting
polycarbonate. In addition to its noise reducing qualities, this set up
enjoys a high level of thermal insulation permitting the use of a less
powerful air-conditioning system. Misting up is not a problem
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A domino seating arrangement
To
distance itself from conventional saloon designs, the D5 does not copy
the interior layouts of monospaces which supplanted them. It improves
on them with an idea that will bring much user-friendliness on board:
the central seat slides and swivels. Moved back, it forms a bench with
the two others, sliding between them. By moving it fully forward (90
cm), the central passenger can join the passengers at the front and
even stretch his or her legs, in this respect D5 resembles its ancestor
which lacked a central console. Once centred, this seat with integral
belt can be turned round to face the rear making it possible to
converse with the two passengers in the back. All three individual
seats may be easily folded and dismounted thanks to their monorail
mountings as already seen on the new Renault Scespace to increase the
boot capacity, The rear boot has a capacity of only 400 litres because
of the “variator” or electronic control unit, but as one could expect,
the bonnet conceals a second boot of 300 litres, unless one opts
for the RunFlat emergency tyre in which case the capacity is reduced to
200 litres.
A hybrid version with integral transmission
Some
D5 versions will however be front-engined – with two engines – one in
each front wheel developing 30 kw each - the hybrid version Hy. Rather
than a sophisticated transmission, whereby the driven wheels are
powered by both a conventional engine and/or an electric motor as
pioneered in the Prius, Citroên distributes them between front and
rear. Equipped with an integral transmission. D5 Hy will be
electric powered up to 70 kph (44 mph) or under strong acceleration,
and integral transmission beyond that. The three cylinders diesel only
drives the rear wheels. The alternator which charges the
batteries is located under the front boot floor. The synchronisation of
the two transmissions is managed by electronics - the variator – for
example the diesel engine is engaged in slippery conditions. Thus
equipped, Hy achieves 3,5 1 per 100 km on average or 4,5 1 as we
measured it... It is hardly better than the 4 1 announced for the
thermal HCDI 1.2 litre, but one can hardly compare the 80 kw of the
latter with the total of 140 kw and 800 N m (81,5 mkg!) of the Hy. A
more modest hybrid may be marketed in 2014 or 2015, once the mixed
turbine GNV/gas oil brought in as a dowry by Honda has been fully
developed.
A 100% pneumatic suspension
Four
wheel drive, self-levelling and variable ride height suspension (as on
all large Citroêns since 1955) meant that Citroên had to battle with
the ministry for the Economy and the Environment to exonerate its D5 Hy
from the 4x4 tax since in high position, it can take on the most rutted
surface. D5 gives up hydropneumatic suspension for an original 100 %
pneumatic suspension which promises, in addition to new levels of
comfort, some strange noises to judge some by the strange one hissing
emitted by the beautiful one when the car was presented to the press.
Unlike the BMW which has used pneumatic shock absorbers on its motor
bikes since 2005, those of D5 are controlled via two bottles of
compressed air supplied by a compressor, the noises of which will
trigger familiar memories to those who had the privilege to pilot a
DS.
Less innovative since already seen in the competition
The
D5 will offer some rather refined options. Thus, the electrochromatic
glasshouse which switches from perfect transparency to total opacity in
6 seconds will be available, a whim of Julien Jodry imposed on Saint
Gobain, to switch from black to a creamy white. An amusing detail, the
rear view cameras are located where the DS placed its rear indicators.
Two plasma screens were intended to replace the rear view mirrors but
the Paneuropean Homologation Commission rejected this, as it recently
did steer-by-wire, butter-derived fuel oil and TV screen windscreens.
Traditional mirrors had to be borrowed from an old Citroên prototype
from the early 21st century - Airdream.
It
remains to test the D5 on our good old Montlhéry circuit (recently
classified as a world inheritance site by UNESCO) and maybe even on the
road, as soon as one of our testers recovers his licence. It will be in
our next edition, in the shops on November 24, 2012, and on your
téléphonets the evening before.
Acknowledgments:
Author - JEAN SAVARY
Art – JULIEN JODRY
Translation – JULIAN MARSH
Originally published by ACTION AUTO MOTO
AUGUST 2005
© 2005 JEAN SAVARY, JULIEN JODRY, ACTION AUTO MOTO,
JULIAN MARSH
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