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Friday, September 11, 2009

Fiat 500 engine technology

Fiat SGE-Twin Cylinder- 900cc Turbo - bifuel (gasoline/CNG hydrogen blend)
8 valves - 105 HP with Multiair technology

In Europe, the Fiat 500 comes with a choice of modern engines, each one offering great performance, excellent fuel economy and low emissions. There are two gasoline units (the 69 bhp 1.2 8 valve and 100 bhp 1.4 16 valve) and one Multijet turbo diesel, the 75 bhp 1.3 16 valve. In addition the Fiat 500 Abarth has a 1.4 16 valve turbocharged engine that puts out, depending on version, 135 bhp to 190 bhp.

However, what engines we'll see in America is still up in the air. By the time the 500 shows up in early 2011 model year the new Fiat SGE (Small Gas Engine) family of engines will be available. This engine is based on a cylinder displacement of 450cc and, in its most talked about version, it's a 900cc bicylinder normally aspirated or turbocharged unit. Initially horsepower is thought to be at four levels, 65, 80, 90 and 105 bhp. You can read more about what makes the Fiat SGE technology special here.

What is known is that Fiat needs to send us the most powerful versions to succeed here. The 900cc SGE bicylinder MultiAir Turbo with 105 bhp is equivalent to the 1.4 16v 100 bhp engine output wise, but the SGE should be more enjoyable due to the MultiAir system boosting torque. This is a good start but 115 bhp would be better.

The Fiat 500 Abarth currently with 135 bhp would not be sufficient to compete with the cars in its presumed price range (low to mid $20,000's). In this country, it's alway been a horsepower race. The $21,950 Mini has 172 bhp, the $23,230 VW GTI has 200 bhp and the $22,740 Mazda Speed 3 has 263 bhp (of course if the Abarth came in under $20,000, 135 bhp would look better). We could speculate that the Abarth will use the 1.4 16v MultiAir Turbo unit out of the Alfa Romeo MiTo Quadrifoglio Verde that is rated at 170 bhp.

But wait, this is speculative because we don't know what, when or if there will be a performance version of the SGE. We do know there will be multi cylinder versions and if we use a basic formula, a tricylinder SGE turbo of 1350cc will bring 157 bhp at the same level of tune as the bicylinder SGE turbo. Smaller, lighter engines that make more power (and get better fuel mileage) are a good thing, especially in an already light vehicle. At this power level the Abarth will be competitive.

All this will be hashed out during the coming year and it promises to be exciting. In the meanwhile, below is the press release describing the current Fiat 500 engines available. This knowledge will prime us for the next generation of engine technology Fiat is introducing next week and in the coming months.

Fiat 500 engine technology

The Fiat 500 comes with a choice of superb modern engines that guarantee sparkling performance. There are two petrol units (the 69 bhp 1.2 8v and 100 bhp 1.4 16v) and one Multijet turbo diesel, the 75 bhp 1.3 16v with DPF. Each offers different features, all of which are exploited fully by combining them with mechanical 5 or 6 speed gearboxes (a Dualogic sequential robotized 5-speed gearbox will also be available at a later date for the petrol engines), and they stand out for their generosity, brilliant temperament, top performance and advanced technology. However they all also share top reliability and respect for the environment. This has been demonstrated in over 1,600,000 km (1 million miles) that the test cars have already traveled, which will become 2,350,000 km (1.460 million miles) with the last tests.

We should underline that all the engines are Euro 4-compliant and are designed to meet the even stricter limitations of future European standards (Euro 5), already meeting the emissions limits that will presumably be enforced in 2009. The 1.3 Multijet is also equipped with a particulate trap (PDF) as standard equipment.

All the engines mounted on the Fiat 500 are manufactured by Fiat Powertrain Technologies, the Group’s new sector. FPT draws together all the activities in the fields of innovation, research, design and manufacture related to engines and gearboxes for all types of applications: from cars to commercial vehicles, boats and agricultural machinery. With approximately 19,000 employees, 17 plants and 10 research centers in eight different countries, the Sector is one of the world’s most important organizations in its field. At FPT, approximately 3000 highly specialized technicians focus on the development and engineering of innovative technologies. More than 40 patents are filed each year, confirming the quality and seriousness of this commitment, and making FPT a huge centre of technological excellence and ongoing innovation.

The 69 bhp Fire 1.2 8v

Fiat 1.2 8 valve engine

The tried and tested Fire (Fully Integrated Robotized Engine) engine that will power the Fiat 500 has a capacity of 1242 cc, and has undergone a series of refinements designed to make it a champion of fuel economy, but without detracting from performance. The engine delivers 51 kW (69 bhp) at 5500 rpm, and peak torque of 102 Nm (10.4 kgm) at 3000 rpm, with a top speed of 160 km/h. That is not all. With the 1.2 8v engine, the Fiat 500 leads its class for consumption, delivering 5.1 l/100 km in the combined cycle, with CO2 emissions of 119 g/km. Acceleration over 100 meters is also excellent at 12.9 seconds.

This figure is even more significant in view of the car’s low consumption. The credit goes to the structure of the engine, which achieves a generous torque at low revs (this makes for more enjoyable driving and outstanding flexibility) and ratios chosen to highlight fuel economy.

A sparkling engine that is sparing on fuel. This has been achieved thanks essentially to:

1) The adoption of an electronic throttle valve control system known as ‘drive by wire’ (with no mechanical connection between the accelerator and the throttle), while it is the electronic control unit that delivers the torque on the basis of the driver’s demands (torque-based system).

2) Fluid dynamic optimization achieved by a new high turbulence combustion chamber combined with a continuous variable cam phaser. This innovative system allows a substantial part of the exhaust gases (about 25%) to be recirculated in the combustion chamber, significantly reducing fuel consumption and exhaust emissions when driving with a partial load.

3) The timing components have been made lighter and the valve springs are of the low load type, to reduce friction.

Another interesting feature of this engine where fuel consumption is concerned, is the use of an active knock sensor capable of managing the advance in the best possible way in all conditions and, above all, the multi point sequential phased injection system by Magneti Marelli.

The quality of life on board has also been improved by optimizing the performance of the intake and exhaust systems, optimizing the coupling play between the crankshaft and crankcase, through the computerized selection of the main bearings, and the development of a specific installation of the engine in the engine bay.

This keeps the transmission of vibration from the engine to the body shell to a minimum. A special engine support system has been adopted, that comprises two blocks and a reaction link, which acts as a tie rod, in which the new bearings are aligned on an axis that goes through the engine’s center of gravity in order to obtain reaction forces with a neutral arm.

On the environmental front, the 1.2 8v fits a catalytic converter in the engine bay, welded to the exhaust manifold flange. In this position the device is extremely efficient because it reaches high temperatures very rapidly thus abating emissions even while the engine is warming up.

The engine has been made even more reliable. The coils have been mounted closer together in a single block. This new type of coil means less spark plug wear, more energy available to ignite each plug thanks to the elimination of the lost spark, better cold starting due to the additional energy available for the spark plug (more energy supplied by the coil and no losses caused by the transfer of high voltage due to the adoption of very short cables), and finally, a significant reduction in the risk of disturbance to the on board instruments due to high voltage cables.

The 75 bhp 1.3 Multijet 16v

Fiat 1.3 Multijet 16v Turbo Diesel engine

The Fiat 500 would not be complete without the 1.3 16v Multijet engine, the smallest and most advanced second generation direct injection Common rail diesel unit, of which more than two million have been built to date.

Fitted with a Borg-Warner fixed geometry turbo (of the waste-gate type) with an intercooler, the engine delivers a maximum of 75 bhp (55 kW at 4000 rpm) and torque of 14.8 kgm (145 Nm) at 1500 rpm. With this engine, the Fiat 500 guarantees excellent performance: it has a top speed of 165 km/h and accelerates from 0 to 100 km/h in 12.5 seconds.

Fuel consumption is also among the best for this segment: 5.3 l/100 km in the urban cycle, 3.6 l/100 km out of town and 4.2 l/100 km in the combined cycle, and CO2 emissions are among the lowest on the market at just 111 g/km.

The engine is a straight-4 with a capacity of 1248 cc, a bore of 69.6 mm and a ‘long’ stroke of 82 mm. There are four valves per cylinder, governed directly by a twin overhead camshaft with maintenance-free hydraulic tappets and automatic play take-up.

That is not all. The 1.3 Multijet 16v is a miniature masterpiece: ‘dressed’ with all its accessories, it weighs just 130 kg, it is small, just 50 cm long and 65 cm tall, and the component layout was designed to take up as little space as possible.

Designed by criteria of maximum rationality, efficiency and reliability, the engine guarantees excellent efficiency and is practically ‘for life’: it was designed to travel 250,000 km without needing any maintenance to the mechanical components.
The compact, sophisticated engine is also extremely eco-friendly, thanks to an emissions control system that envisages an EGR valve triggered electronically and managed directly by the engine control system, a heat exchanger to cool recirculating exhaust gas (EGR) and a ‘close coupled’ catalytic converter.

A particulate trap (DPF), the ‘for life’ system that abates fine dust and does not need additives to be regenerated, is standard equipment.

The 75 bhp 1.3 Multijet 16v therefore represents a technological leap forward which, for the customer, translates into lower consumption and emissions, without even taking into consideration the reduction in noise (due to the multiple injections), the increase in comfort (fewer alternating masses means less vibration), the smooth, responsive steering (due to the really smooth torque delivery, which is guaranteed by the improved combustion control), the elasticity and prompt response of a diesel that resembles a petrol engine for the vast excursion in the number of revs (for example, you are no longer aware of the fuel ‘cut-out’ just above 4000 rpm), and the ecological elements that enhance the diesel’s main environmental credentials (consumption) while minimizing its main defect (particulate emissions).

The 100 bhp 1.4 16v Fire engine

Fiat 1.4 16v Fire engine

One hundred horsepower on hand on such a compact car points up a brilliant, agile character, which allows it to slip easily and cheerfully through congested town traffic. The engine has a capacity of 1368 cc and four cylinders in line, with a bore of 72 mm and stroke of 84 mm.

There are four valves per cylinder, driven directly by the overhead camshaft. The engine was developed focusing particular attention on performance and consumption, fields in which the Fiat 500 leads its class. All credit to the volumetric efficiency which has been optimized throughout the operating range, thanks to careful fluid dynamic development of the entire intake system and timing phasing.

The 1.4 16v delivers a maximum of 73.5 kW (100 bhp) at 6000 rpm and peak torque of 131 Nm (13.4 kgm) at 4250 rpm. Performance is excellent: the new car has a top speed of 182 km/h, and accelerates from 0 to 100 km/h in 10.5 seconds. It is a sparkling engine with excellent performance enhanced by an electronic throttle valve control system known as ‘drive by wire’.

This engine also proposes a number of changes that help to keep consumption down. For example, the timing components have been made lighter and the valve springs are of the low load type, to reduce friction.

Other features of the new 1.4 16v Fire are the increased compression ratio and the generous torque at low engine speeds, characteristics that have made it possible to limit consumption: for example, in the combined cycle it returns 6.3 l/100 km. This target was achieved by the calibration of the latest generation engine control system, which succeeded in reducing consumption as much as possible, compatible with the requirements of drive ability, performance and emissions.

In order to guarantee low emissions, special injectors have been adopted that optimize the spray phase, thus reducing the quantity of petrol that adheres to the walls of the intake manifold during cold starting and in transients (when you depress the accelerator). This reduces the quantity of hydrocarbons in the exhaust, guaranteeing respect for the environment and for increasingly stringent legislation.

Press release thanks to Fiat Group Press


Anonymous said...

Why does the 1.4 USA version have to use premium fuel and feature unremarkable economy for such a small car/engine combination. Several larger cars and even less expensive cars offer 30/40-42 mpg and achieve those ratings with an automatic transmission. With automatic, the 500 drops mpg severely. I'm just curious. said...

The 1.4 does not need premium. It is recommended but not required.

This car is tuned for drivability and fun, not maximum fuel economy. It isn't that kind of car. However, people do easily exceed the EPA ratings and get over 40 mpg. Go to the forum and see the real world mpg: