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This is part of the ItalianCar.net archive - go to ItalianCar.net now NEWS ARCHIVE Alfa's first diesel in Oz
Alfa have recently announced their first diesel car for the Australian market - the Alfa 147 JTD - a car they claim offers better acceleration than its larger engined petrol counterpart while using little more than half the fuel, Full deliveries won't start until January, but ten lucky Australians will be able to get behind the wheel of this unique car in time for Christmas. "The first delivery of the 147 JTD M-JET has just arrived and, such has been the demand for this outstanding performer, we can't keep them locked up until the full stock arrives in January," says David Stone, General Manager of Alfa in Australia. "So we are releasing the first batch of cars and that means ten lucky Australians are going to be able to have a faster, more economical and environmentally friendly Christmas." Although the 147 JTD is the first diesel powered Alfa to arrive in Australia, Alfa already has a good reputation with diesel powered cars and, indeed, worldwide, diesel accounts for 76 per cent of their sales. The combination of performance, luxury and style with fuel consumption economy while cutting carbon dioxide emissions has been a winning formula for Alfa. Although the diesel engine is, at 1.9 litres, slight smaller than its petrol counterpart, the 2.0 litre Twin Spark engine, they both produce same power, 110 kW. But it is when it comes to torque that the JTD engine really punches above its weight. Compared to the Twin Spark engine's 181 Nm of torque, the 1.9 JTD unique produces an epic 305 Nm, or, to look at it another way, 5 Nm more torque than the 3.2 V6 engine in the 147 GTA. Of course, this translates into performance: the 147 JTD is quicker to 100 kmh by half a second compared to the petrol car and goes on to the same 208 kmh top speed. The huge torque figure and the low engine speed at which it is achieved means that the 147 JTD offers remarkable in-gear performance right across the speed range.
But the 147 JTD does not just offer superior performance. On the open road, the 147 JTD is using just 4.7 litres per 100 kmh or 60 mpg in the old money, a figure normally reserved for the slowest, smallest econo-boxes. There's more good news when it comes to emissions, too. Carbon Dioxide emissions, the so-called Greenhouse Gas, are slashed from more than 210 grams per km to just 157. The fact that the 1.9 litre JTD engine is also unusually light and compact not only enhances economy, it also further improves handling and roadholding as it reduces weight over the front wheels and enables even more effective use of that 305 Nm of torque. So how is this astonishing combination of performance and economy achieved? The answer is simple. With the use of the most advanced diesel engine available. The Fiat Group invented what has become known as common rail, direct injection diesel engines, but which are more correctly known as Unijet. The next generation of engines are called Multijet and, as the name suggests, each cylinder now gets an injector with six, rather than one hole, allowing for more efficient and effective fuel burn. The turbocharger is a variable displacement unit that can offer the lag-free, low engine speed operation of a small turbo, while at the same time being able to generate increased boost at high revs without getting breathless. And the only place that this technology is available is from Alfa. While the Fiat Group has licensed Bosch to produce Unijet for a wide range of other car makers, Multijet remains the preserve of Alfa. The 147 JTD has the same equipment and feature list as the five door 147 TS and is priced at an RRP of $39,990. Alfa considers the JTD to be a 'better' car than its petrol equivalent since it outperforms it and runs on less fuel. It also comes with a six speed gearbox. "The Alfa Romeo 147 JTD is truly a car the like of which has not been seen in Australia before," says David Stone. "On one hand it offers the economy and emissions of the smallest, most efficient economy car, while on the other it has the performance of true hot hatch and its driving dynamics, a combination of an agile chassis, a light engine and a huge torque punch at low revs means its drives not just like an Alfa Romeo should but some have said even better. In December just ten lucky drivers will have this experience, but we believe once the word gets out about just what an incredible car the 147 JTD is, they will be joined hundreds of others!"
The 1.9 litre 110 kW 16 valve JTD M-JET engine For example, the Common Rail system used on the 1.9 JTD 16v M-JET includes two new strategies for automatically calibrating and balancing the diesel injected to lower noise and reduce vibration. It goes without saying that, so equipped, the New Alfa 147 guarantees extremely attractive performance figures: the top speed is 208 km/h and acceleration from 0 - 100 km/h takes place in 8.8 seconds. All this comes
with very frugal fuel consumption: These results are not to be underestimated, particularly because they are obtained with an engine that represents an incredible leap forward from prechamber diesels and even improves on first generation JTD engines. The secret of the Multijet engine lies in the control unit that governs the electric injector opening and closure system (and also in the injectors themselves). The crucial element is the electronic control unit itself that can perform a set of injections that may be very closely spaced. Fiat Auto's researchers developed the parts (together with the injectors) especially for this application. It is designed to deliver the multiple injections that assure the designer more accurate control of pressures and temperatures developed inside the combustion chamber and also more efficient use of air taken into the cylinders. This enables further goals to be achieved: quieter combustion, reduced emissions and increased performance. The Multijet system is underpinned by long years of research. Fiat engineers began by resolving the problem of limits imposed by the control units. Then they went on to map the benefits they could achieve by plotting different multiple injection sequences (two secondary injections very close to the main injection; one secondary injection not too close to the main injection plus two closely-spaced secondary injections; one secondary injection and then two main injections close together after a certain period etc.) against different engine service conditions: idling; with low loads and low rpm; with high rpm and moderate load; with low rpm and high load etc. The study revealed the potential of the system and showed that great benefits are achievable in all cases, though these tend to focus on one field or another according to the type of sequence chosen and the engine service area targeted. In some cases, for example, the priority is to reduce start-up times and fume levels, in other cases it is to increase torque and reduce noise while in others it is to reduce emissions and ensure a quieter drive. This research strand has led to the creation of the Multijet engines: another first for the Fiat Group in the diesel engine field. But we had been putting in a lot of hard work behind the scenes since 1986, the date that marked the arrival of the Croma TDI, the first direct injection diesel vehicle in the world. At that time, this represented a true engineering breakthrough that was later adopted by other manufacturers. Direct diesel injection engines offered better performance and lower fuel consumption but failed to resolve the problem of excessive engine noise at low rpms and while speeding up or slowing down. So work began on a more advanced direct injection system and a few years later this led to the development of the Common Rail principle and the Unijet system. The idea first came from the Zurich University research laboratories where scientists were working on an injection system that had never before been applied to a vehicle, i.e. the Common Rail system. The idea is simple yet revolutionary. If you continue to push diesel into a tank, the pressure inside will rise and the tank itself will become a hydraulic accumulator (or rail), i.e. a reserve of pressurised fuel ready for use. Three years later, in 1990, the Unijet system developed by Magneti Marelli, Fiat Research Centre and Elasis on the Common Rail principle entered the pre-production stage. This stage was complete in 1994, when Fiat Auto started to look for a partner with superlative knowledge of diesel engine injection systems. The final stage of the project, i.e. completion of development and industrial production, was eventually entrusted to Robert Bosch. In 1997 the Alfa 156 JTD arrived with its revolutionary turbodiesel engine. Compared to conventional diesel power units, the JTD guarantees an average improvement in performance of 12% together with a 15% reduction in fuel consumption. These results meant that cars fitted with the engine were an immediate hit. Now the time is ripe for the second generation of JTD engines, the Multijet and multivalve units: in 2002 with the 1.9 16v M-JET (forerunner of this new family of multipoint injection engines) in 2003 with the 1.9 upgraded to 150 bhp for the Alfa GT and the 129 kW (175 bhp) 2.4 JTD Multijet 20v available on Alfa 166, Alfa 156 and Sportwagon models. Now comes the turn of the New Alfa 147 to enjoy all the benefits of the 150 bhp/110 kW 1.9 JTD 16v M-JET.
© italiancar.com.au 15/12/05
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