2014 Jaguar Lightweight E-Type
Jaguar has revealed the prototype of its 'new' Lightweight E-type - a
further six of which will be built and sold.
Jaguar announced in May 2014 that it would recreate six new Lightweights,
each built by Jaguar Heritage, part of Jaguar Land Rover's new Special
Operations division.
Each of the six cars will be built to a specification originated from the
last Lightweight E-type produced in 1964 and will be hand-crafted at the
original home of the E-type, Jaguar's Browns Lane plant in Coventry, England.
The cars will be sold as period competition vehicles and all will be suitable
for FIA homologation for historic motorsport purposes.
The new cars are the 'missing' six vehicles from the 'Special GT E-type'
project, which originally started in February 1963 with the objective of
building 18 cars. Only 12 of the aluminium-bodied Lightweight E-types were
eventually built and the remaining six designated chassis numbers having lain
dormant, until now. The six new cars will carry those original, historic
Lightweight E-type chassis numbers.
A race winner in the hands of a variety of famous drivers during its short
competitive career, the car has achieved worldwide fame and original examples
are now valued in the many millions. In recreating the Lightweight E-type,
Jaguar Heritage has been able to call on the superlative skills and experience
of many talented engineers and technicians already working in a variety of
departments within Jaguar.
All, when offered the chance to assist with this unique project, leapt at
the opportunity. Some even have an indirect link with the E-type when it was
new: one master technician calculated that his family - including his
grandparents, his father and his uncle - had a collective 170 years' service at
Jaguar stretching back to the early 1960s.
The expertise and attention brought to bear on this recreation project is
staggering, with the full resources of Jaguar being applied to ensure that the
six new Lightweights will not only be authentic, but will also be built to the
highest quality standards.
So the six chosen customers will each receive the rarest of things - a
brand new Lightweight E-type, hand-built at Browns Lane and just as desirable
as one of the originals.
"Operating from a brand new workshop at Browns Lane - now open for the
restoration and servicing of customer cars - the building of six new,
meticulously crafted Lightweight E-type period competition cars by Jaguar
Heritage is testament to the unique skills within the team. To know those same
skills can also be utilised to the benefit of existing classic Jaguar owners
means this is a very exciting time for Jaguar Heritage."
Derek Weale, Director, Jaguar Heritage Business
THE LIGHTWEIGHT E-TYPE PROJECT IN DETAIL
Engineering:The bodyshell
The core component of the Lightweight E-type is its aluminium bodyshell.
This material replaced the steel of the production E-type in the quest to shed
weight - some 250lb (114kg) were saved compared with the standard car.
Despite the 50-year gap, the aluminium build of the six new Lightweights
gives them an immediate affinity with the current Jaguar range, the F-TYPE and
XJ models being built to exacting standards with aluminium bodies for exactly
the same reason. In fact, Jaguar is now the world's leading manufacturer of
aluminium-bodied cars and the company has unrivalled experience in the
relatively new field of applying aluminium technology to volume production
cars.
So when tasked with the job of recreating the Lightweight E-type's
aluminium body, today's Jaguar engineers could relate at once to what their
predecessors had achieved 50 years before. However, despite the enormous
advances in technology since the early 1960s, the decision was taken not to
incorporate modern materials or fixing methods. While high-strength aluminium
alloys and bonded structures would have been invisible, they would not have
been true to the original design - and nor would they have conformed to the
FIA's homologation requirements for historic racing.
Instead, today's advanced technology was deployed to ensure the highest
quality and most faithful rendition of the Lightweight E-type's open two-seater
body components. Using state-of-the-art scanning technology, the inner and
outer surfaces of a Lightweight bodyshell were digitally mapped.
The resulting massively detailed scan, which recorded dimensions and shape
down to a fraction of a millimetre, was then assessed by Jaguar's technicians
to validate how the body was assembled back in the 1960s, how consistent the
structure was side-to-side, and how it could be engineered today to produce the
highest quality result for the Lightweight E-type project.
As this digital capturing process gave Jaguar's engineers complete control
over the Lightweight E-type body's 230 individual components, their shapes
could then be optimised before the data was sent to the tool room at Jaguar's
Whitley engineering centre. Even panels which are unseen within the structure
have been faithfully reproduced. To ensure absolute symmetry, one side of the
scanned body was used as the datum, this being 'flipped' to produce an
identical condition on the opposite side.
Additionally, before being signed-off, the outer 'A-surface' CAD scan was
transferred to Jaguar's design department where the surface geometry was
finalised. All this work ensured that the tooling from which the majority of
the new body parts are produced is as accurate as possible.
Approximately 75 per cent of the panels are made in-house at Whitley, just
a few very large pressings being supplied by external specialists using
Jaguar-designed tooling. The grades of aluminium used for both the
under-structure and surface panels are almost identical in mechanical
properties to those used for the original 1963 Lightweight E-types. The body is
completed to original Lightweight E-type Chassis no. 12 condition, by which
time Jaguar had added some additional strengthening in key areas of the shell.
The aluminium body is then completed by the addition of an aluminium bonnet,
doors and trunk lid. As with the original cars, an aluminium hard top is
standard.
The development of the body-in-white tooling was undertaken by the same
department that builds all Jaguar Land Rover prototype vehicles, so the
expertise applied to the project was world-class. The build process and
assembly procedures were initially proved out on Car Zero; this is effectively
an engineering prototype and will not carry one of the six Lightweight chassis
numbers.
For the Lightweight E-type project, Jaguar's engineers created a 'grey
book' of the type used during the development of new production Jaguars. This
internal document sets out the required quality standards in terms of bodyshell
fit-and-finish and ensures a consistency of build quality for all six new
Lightweight E-types.
A roll-over cage is fitted as standard, and the body includes mounting
points for a detachable front extension which is available as an extra. The
cars are built in a form suitable for FIA homologation for historic motorsport
purposes (see full specification).
The engine and drivetrain
The Lightweight E-type was powered by a highly developed version of
Jaguar's straight-six XK engine which, with its chain-driven twin overhead
camshafts and aluminium head with hemispherical combustion chambers, remained
highly advanced in 1963 even though it had first been seen in the XK 120 as far
back as 1948.
It was this engine that had powered the C- and D-types to five Le Mans
victories in the 1950s, and the unit developed for the Lightweight E-type is
based on the 3,868cc (236 cu in) engine which, in the D-type, had won Le Mans
in 1957. A similar big valve 'wide angle' cylinder head is used, but in place
of the D-type's cast iron block, Jaguar introduced an aluminium block for the
Lightweight E-type which substantially reduced the amount of weight over the
front wheels. This also features in the present-day car, with pressed-in steel
liners.
Another major feature transferred from the D-type is the dry sump
lubrication system. This uses a scavenge pump to collect oil from the sump and
return it to a separate oil tank in the underbonnet area. This eliminates oil
surge during fast cornering and consequent risk of damage to the engine's bearings,
and also allows a greater quantity of oil to be carried.
The compression ratio is 10:1 and today's car is supplied with three 45DCO3
Weber carburettors. These were homologated by Jaguar for the Lightweight E-type
in addition to a Lucas mechanical fuel injection system - which is being
offered to customers as a cost-option (and which is fitted to Car Zero). The
exhaust manifold is a steel fabrication and leads the exhaust gasses into twin
pipes which take them through a centre silencer box to the rear of the car,
where the exhaust system ends in twin polished tail pipes.
Whether carburettors or fuel injection is specified, brake horsepower is
well over 300, and with torque in the region of 280lb ft at 4500 rpm, the car
is endowed with rapid acceleration from comparatively low engine revs - a
traditional feature of Jaguar racing engines.
A 12 volt negative earth electrical system is used, and the engine benefits
from a modern inertia-type starter motor. The water and oil radiators are in
aluminium alloy, there is an aluminium expansion tank for the coolant, and the
fuel tank is mesh-filled for safety.
The power is transferred to the road via a lightweight, low inertia
flywheel, a single-plate clutch and a Jaguar close-ratio, manual four-speed
all-synchromesh gearbox as used by the Lightweight E-type in period. A variety
of final drive ratios are available, all with the Powr-Lok limited-slip
differential, but a 3.31:1 ratio is supplied as standard.
Suspension, steering and brakes
The twin wishbone front suspension and independent wide-based wishbone rear
suspension (where the drive-shaft serves as the upper link) are set-up
according to period racing practice, with uprated shock absorbers controlling
the torsion bar springs (front) and the four coil springs (rear).
The steering is the excellent standard E-type rack-and-pinion, with a
traditional wood-rim wheel for the driver. Larger (12.25in) brake discs are
fitted at the front, with the rear brakes being standard E-type. No servo is
fitted.
The 15in diameter wheels are period type in the correct 'perforated' style,
and like the originals are cast in magnesium alloy. Rim width is 7in front, 8in
rear. Dunlop racing tyres are fitted, 6.00 section front, 6.50 section rear,
both in CR65 compound.
Final assembly
The monocoque bodyshell is built at Whitley where it is mated to its
tubular engine sub-frame - which is stiffened with gussets as for the original
Lightweight - and then shipped to Jaguar's Gaydon facility for painting. From
there it is then taken to Jaguar Heritage at Browns Lane where the car is built
up with powertrain, suspension, brakes, steering, electrical items, instrument
panel and soft trim.
This process takes place in a dedicated area close to where the original
Lightweight E-types were assembled in 1963/64, and the work is undertaken by
highly skilled technicians used to assembling extremely complex JLR prototypes.
It is at this stage that personal consultation with the customer dictates
the final specification for each individual car - no two of which are expected
to be identical.
Car Zero underwent a 15-day shake-down period at Jaguar Land Rover's test
facility at Gaydon to prove out the car's dynamics and establish optimum
suspension settings. This involved Mike Cross, Jaguar's Chief Engineer, Vehicle
Integrity. Jaguar's engineers even established a 'design verification plan' for
the car, just as they would do for an entirely new model. Each of the six new
Lightweights will go through shake-down tests to ensure that they meet the
required standards in terms of braking, handling and steering. "In our
contemporary Jaguar sports cars our aim is always to achieve an immediacy of
response to all driver inputs - and the goal with Lightweight E-type was the
same. For me, its response to steering, brake and throttle inputs - along with
the terrific noise it creates - is what makes it such an engaging machine from
the driver's seat."
Mike Cross, Chief Engineer, Vehicle Integrity, Jaguar
Design
Jaguar's Advanced Design Studio has been involved in the project from an
early stage, charged with arriving at the appropriate level of trim for the new
car, together with selecting the materials used and the nature and colour of
finishes.
"With the Lightweight E-type, our focus as a design team has been to
ensure justice was done to the original work of Sir William Lyons and Malcolm
Sayer. Meticulous attention to detail has been everything to us in re-creating
this car, just as it is in our contemporary Jaguars. I believe the result is a
new Lightweight E-type that is as stunning now as the originals would have been
when they were new."
Ian Callum, Director of Design, Jaguar
Connolly leather is used, supplied by Jonathan Connolly with hides produced
to the same specification as those used by Jaguar in the 1960s. This leather is
used to trim the competition-type aluminium bucket seat base. The centre
console covering is also leather, and there is a choice of seven trim colours.
As befits a thoroughbred GT car where weight saving in all areas is
demanded, interior trim is minimal. However, the customer can opt for a more
fully-trimmed car and the Jaguar team can devise bespoke trim packages. This
may include door cards, headliner for the hardtop, removable custom
saddle-leather floor mats, and a cover for the transmission tunnel.
Much of Car Zero's interior - floorpan, sills, rear areas - have
intentionally been left unpainted, to emphasise the car's aluminium bodywork.
The studio has also selected a palette of six 'heritage' paint colours
recommended for the exterior: Carmine red, opalescent grey metallic, silver
metallic, opalescent blue metallic, British racing green, Old English white.
However, various colour and trim alternatives are available, as each car is
built to the personal specification of each individual customer, who can
discuss options with Jaguar's Director of Design, Ian Callum, in person.
In celebration of the new Lightweight E-types, Jaguar has also furthered
its relationship with the Bremont Watch Company. Bremont will create six
bespoke 'E-type' watches, each of which will be offered to customers of the six
new Lightweight E-types.
Source:Jaguar Press
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