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New Jaguar XF Diesel S
11th January, 2009
"The new XF V6 Diesel S - combining superb performance and excellent fuel economy - sets the pace with
acceleration from 0-100 km/h in 6.4 seconds, a maximum speed of 250 km/h, yet delivers an average fuel consumption
of 6.8 litres/100 km and CO2 emissions of 179 grammes/kilometre: Truly the best of both worlds!"
..... Mike O'Driscoll, Managing Director, Jaguar Cars.
The New Jaguar XF Diesel S - In Brief
- The most advanced, powerful and efficient Jaguar diesel ever
- New 202 kW high-performance XF Diesel S featuring Jaguar's new AJ-V6D Gen III S 3.0-litre diesel engine
delivers a massive 600 Nm of torque
- 0-100 km/h in just 6.4 seconds, a maximum speed of 250 km/h and fuel economy of just 6.8 litres/100 km
(combined cycle) - 12 per cent better than the acclaimed 2.7 litre V6 diesel engine
- Emits just 179 g/km - a 10 per cent reduction in CO2. Conforms to EU5 emission regulations using conventional
exhaust after-treatment
- 33 per cent more powerful and 61 per cent more torque from 1,500 rpm than the 2.7-litre V6 diesel
"With CO2 emissions of 179 g/km, 6.8 l/100 km average fuel economy and 0-100 km/h acceleration in 6.4
seconds, this is another great example of Jaguar delivering unrivalled performance while at the same time taking
the level of refinement in diesel engines to a whole new level." ..... Mick Mohan, Jaguar Programmes Director.
When it was introduced last year, the XF was recognised as a dramatic expression of a bold new Jaguar design
language. It also soon became apparent that here was a car where the driving experience exceeded the expectations
provided by the appearance. Now, the new XF Diesel S takes this driving experience to new levels, shifting the balance
even further towards dynamic performance while still retaining the XF's core values as a refined and luxurious sports
saloon.
Distinguished by discreet 'S' badging, the car that defines Jaguar sporting luxury is even better for the 2010 model
year, with a new high-performance diesel.
Powered by a 202 kW engine, the Diesel S gives the XF outstanding levels of performance, accelerating from 0-100
km/h in just 6.4 seconds, 1.8 seconds quicker than the 2.7-litre model. Maximum speed is electronically limited to 250
km/h.
Featuring parallel sequential turbochargers to help deliver the high levels of power and torque seamlessly and with
effortless flexibility, this engine is perfectly matched to Jaguar's sophisticated six-speed ZF 6HP28 automatic
transmission.
"The new parallel sequential turbocharger system on our new V6 diesel delivers V8 levels of performance from very
low revs. It's a power unit that offers superb flexibility and remarkably low fuel consumption and emissions, while
building on the refinement that has become a trademark of our Jaguar diesel engines." ..... Ron Lee, Group Chief
Engineer, Powertrain.
The XF 3.0 Diesel will be released in Australia in the 3rd quarter 2009.
The new AJ-V6D Gen III S engine - In detail
Drawing on the experience gained in designing the original, 2.7-litre engine, the new 3.0-litre AJ-V6D Gen III S
diesel demonstrates that it is possible to deliver improved performance, while reducing CO2 emissions and fuel economy.
In the XF, the new engine produces 10 per cent less CO2 than the 2.7-litre, while power has increased by 33 per cent. As
well as tackling CO2, the new 3.0-litre engine meets the forthcoming EU5 regulations, due to come into force at the start
of 2011. And these great performance leaps are achieved with combined average fuel consumption of 6.8 l/100 km - an
improvement on the 2.7-litre engine of 12 per cent.
Twin-turbos - maximum efficiency, instant response
A key feature of the new engine is the unique, parallel sequential turbocharger system, the first of its type to be
fitted to a V-engine anywhere in the world. Delivering high torque throughout the entire engine rev range, improved
throttle response and low CO2 emissions, the twin-turbochargers work sequentially to deliver unrivalled response and
best-in-class torque - an impressive 61 per cent more than the 2.7-litre diesel from 1,500 rpm - while packing a huge
punch at higher engine speeds.
For most day-to-day driving, including motorway cruising, a responsive, variable-geometry primary turbocharger does
all the work, while the smaller, fixed-geometry, secondary turbo is dormant, saving energy and improving efficiency.
When the engine revs climb above 2,800 rpm, the secondary turbo is brought on line within 300 milliseconds, smoothly
and seamlessly boosting the engine output with no discernible turbo-lag or power-step.
Driving a turbocharger requires pressure from the exhaust, providing pumping losses in the engine and increasing
fuel consumption. To alleviate this, valves under the control of the engine management system isolate the secondary
turbocharger both from the exhaust stream and the engine inlet tract when it is not required.
Some twin-turbo systems rely on a smaller turbo for primary use, only using a larger turbo when higher power is
required. Though effective, this has the disadvantage of raised exhaust pressure and increased pumping losses. The
Jaguar system uses a larger, variable-geometry turbocharger more of the time, which not only reduces pumping losses,
but also improves fuel consumption and CO2 emissions.
Jaguar engineers particularly focused on the issue of turbocharger 'lag' at low engine speeds. The new AJ-V6D Gen
III S 3.0-litre diesel significantly out-performs its rivals by delivering 500 Nm of torque in only 500 milliseconds
from idle.
Third-generation common rail
A new common rail fuel-injection system delivers up to five injections on each cycle at a pressure of 2,000 bar.
Each injector tip is perforated by seven holes through which finely atomised fuel is sprayed into the cylinders. The
high-pressure injection increases power, improves economy and reduces both CO2 and particulate emissions. New,
third-generation high-speed piezo injectors allow up to five precise injection events during each combustion cycle,
minimising engine combustion noise.
Piezo crystal 'packs' operate each injector by expanding when an electric current is passed through them. They
react virtually instantaneously but can make a distinctive click when fired, which can add to diesel engine noise at
idle. The crystals in Jaguar's new injectors are fitted nearer the tip, meaning they are mounted deeper inside the
engine providing better sound insulation and quieter operation.
Another new feature of the third-generation fuel-injection system is the metering mode. Traditional diesel common
rail fuel pumps oversupply the injectors, with the surplus being returned to the fuel tank. During this process, fuel
temperature increases and cooling it again consumes considerable amounts of energy. In metering mode, the pump
delivers fuel to the injectors only at the rate required. Consequentially, there is no rise in fuel temperature and
no wasted energy.
Compact, light and clean
The two cylinder heads, with four valves per cylinder, are made from aluminium and the cylinder block is made from
compact graphite iron (CGI). The higher tensile strength of CGI makes it possible to cast a smaller block; some 80 mm
shorter than a conventional 'grey' cast iron equivalent.
The new, water-cooled, exhaust gas recirculation system (EGR), important for reducing pumping losses and emissions
of NOX in a diesel engine, is more efficient and consumes less power than the 2.7-litre unit. The valves that allow
exhaust gas into the system are located on the 'hot side' of the engine nearest the exhaust manifolds; these valves
never cool while the engine is running, so there is no condensation of combustion deposits which occurs on engines
fitted with 'cold side' valves, hence the EGR system always works at maximum efficiency. Since the EGR cooling is so
effective, exhaust gases can bypass the system and return to the exhaust pipes, allowing faster engine warm-up from
start-up and reducing emissions still further.
EU5 emissions regulations have been achieved ahead of the 2011 legislative timetable using conventional diesel
oxidation catalysts and diesel particulate filters (DPFs). NOX levels are reduced at source through the combustion
system design, the addition of the new common rail injection system and the new EGR system with by-pass. As a result,
specialised NOX exhaust after-treatment is unnecessary, avoiding a potential cost and the need to use additional
precious metals in the exhaust system.
Remarkably quiet for a diesel
The CGI cylinder block and new piezo injectors reduce combustion noise in the engine. Multiple, precise injections
of fuel on the combustion stroke also reduce combustion noise and all engine covers including camshaft covers, front
covers and the sump have been optimised to subdue radiated noise. Engine enclosures have been ribbed to minimise
radiated noise and the sump pan is manufactured from sound deadening steel, comprising a polymer layer sandwiched
between two layers of steel.
Internal friction, a major contributor to unnecessary fuel consumption, has been addressed by careful optimisation
of the crankshaft, valves and pistons. All these features combine to make the new Jaguar AJ-V6D Gen III S engine amongst
the quietest premium diesels on the market.
A major step forward
With its parallel sequential turbocharger system, third-generation common rail fuel injection system and fully
optimised EGR system, the new 3.0-litre AJ-V6D Gen III S diesel sets new class standards when it comes to power, response
and refinement in the premium diesel segment.
"The new XF challenges the rules and redefines Jaguar sporting luxury. Our designers and engineers have worked
together to develop elegant, inspired solutions to complex technical challenges. It's a simple but very effective
philosophy and the result is great new products like the new 3.0-litre diesel XF." ..... Mike O'Driscoll, Managing
Director, Jaguar Cars.
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