One of the second-generation Multijet, multivalve turbo diesel engines, the new 1.6 Multijet has 4 cylinders in line, 16 valves, a displacement of 1598 cc with a bore of 79.5 mm and a stroke of 80.5 mm. Two different engines will be produced: the first with 105 bhp at 4000 rpm and torque of 290 Nm at 1500 rpm, the second with 120 bhp at 4000 rpm and torque of 300 Nm at 1500 rpm.

The engine is supercharged by an electronically-controlled fixed-geometry turbo compressor (for the 105 bhp version) or variable-geometry (for the 120 bhp), to enhance power output while providing very high torque even at low revs.

Compared to the well-known and very popular 1.9 Multijet 120 bhp, the 1.6 Multijet series represents an important step forward. There are improvements in terms of performance, comfort, emissions and running costs, and there are also considerable advantages: with the same power, torque is improved by almost 25% (1500 rpm) and consumption is reduced by 8% (measured on the NEDC cycle). The car is also noticeably more pleasurable to drive, mainly thanks to the torque available at low revs. These objectives have been achieved mainly thanks to the optimised combustion which exploits the potential of the new injectors to the full. Another factor in the improved performance is the multi-injection system, with 1600 bar in the 1.6 Multijet (in both power versions). The injection adapts to the engine speed, thus optimising performance in terms of perceived power and driveability.

Power and torque at the top of its class

The 1.6 Multijet has outstanding torque output in absolute terms, all the more surprising if we consider the cylinder capacity: the torque of 290 Nm in the 1.6 105 bhp (no less than 300 Nm in the 1.6 120 bhp) makes this engine the top performer among engines with a cylinder capacity of 1.8 litres or less. If we consider the specific torque (divided by cylinder capacity), the 1.6 is the highest-performing engine in the category up to 200 bhp, with the sole exception of “super-sports” engines.

That’s not all. If we consider that the maximum torque is generated at just 1500 rpm, we can instantly see why the 1.6 Multijet is a revolution among modern diesel engines: none of its latest-generation counterparts can offer such high performance at such low revs. In short, the new 1.6 Multijet offers an exciting drive that is not easy to find anywhere else, as can be seen from the acceleration and pick-up values: compared to the excellent 1.9 120 bhp, the 1.6 120 bhp records the same acceleration value (0-100 kph in just 10.5 seconds), and more importantly the pick-up from 80-120 kph in 5th gear is almost 4 seconds less (over 1 second is gained in 6th gear).

Last but not least, the combination of the new injection system with the latest-generation turbos (fixed geometry on the 105 bhp and variable for the 120 bhp) rounds off a truly impressive technological set up. The new turbos use technical features and materials capable of supporting greater thermal and mechanical loads, enabling maximum performance together with total reliability.

Total durability and reliability for significantly lower running costs

The designers were presented with a rather ambitious challenge: to improve the already impressive endurance and reliability of Multijet engines by concentrating on the durability of each component, thus ensuring lower total running costs. Thanks to the decade of experience acquired on the first-generation common rail engines and the 1.3 and 1.9 Multijets, the technicians fulfilled their task by giving the new engine an important first: the 1.6 Multijet is the engine with the longest service intervals. Proof of the high quality achieved on the Bravo and the effort put into improving strength and efficiency through the careful study of each component is that the 1.6 Multijet only needs servicing every 35,000 km, to keep both car and engine in perfect working order. The benefits in terms of lower running costs are obvious: for example, one less service is required over distances travelled of 90,000 or 100,000 km (the distances used most frequently in long-term leasing agreements). This reduces ordinary maintenance costs by around 25%.

The reliability of the 1.6 16v engine is the result of extensive and specific testing on the engine and each component during development. Over 40,000 hours of bench tests were performed between the development stage and industrialisation, with around 1,000,000 km clocked up on the vehicle. The tests were not only aimed at determining the functionality of the parts, but also their durability, and they resulted in very high quality standards. All this was possible thanks to the use of high-value components such as the EGR (Exhaust Gas Recirculation) valve with DC motor, and the glow plugs with low voltage technology. High-resistance materials and alloys were used on critical parts such as ball bearings and piston seal rings.

Eco-friendly engine

One of the technicians’ main priorities was to ensure not only excellent performance but also the lowest possible emissions levels, to reflect the Fiat philosophy. Even today, Fiat is the “full liner” brand with the lowest emissions levels across its entire fleet. Following in the footsteps of the new Fiat 500, the Bravo has also notched up an important record in this field: thanks to the 1.6 Multijet, it is now the first car in its category to be fitted with Euro5-compliant engines, well ahead of the legal deadline. This record has been achieved partly thanks to the use of innovative exhaust gas treatment systems, such as the close coupled diesel particulate filter and the EGR (Exhaust Gas Recirculation) system, which improves temperature control and gas flow while cutting down on emissions and fuel consumption.

As far as the treatment of exhaust gases are concerned, the use of a state of the art device such as the close-coupled DPF is particularly important. The filter effectively integrates the oxidising catalyst and the particulate filter which are now essential elements in the modern concept of a diesel engine. Thanks to the use of new manufacturing technologies and optimisation of the internal flow of burnt gas, the CCDPF creates significant benefits in terms of achieving engine objectives. As far as emissions are concerned, the output of pollutants (HCNOx and particulates) is reduced significantly, compared to the configurations currently on the market. Equally importantly, it improves the stability of particle reduction (known as the DF – deterioration factor) over time.

The compact size of the filter also reduces counter pressure in the exhaust gas and consequently reduces fuel consumption, leading to lower CO2 emissions. As the filter is placed close to the turbine outlet, the average temperature of the incoming gases is higher, thus reducing the amount of diesel needed for “regeneration” (combustion of the deposited particles to avoid blockage of the filter). Also, integration of the two parts reduces the weight, and more importantly the cost of the exhaust system, since improved overall efficiency reduces the quantity of pure materials used. The pairing of these solutions, and the excellent results achieved, is another demonstration of the great strides made by FPT – Fiat Powertrain Technologies, Fiat Group Automobiles and the whole Fiat Group towards greener traffic.

It is worth noting that purchasing the Euro5-compliant Bravo 1.6 Multijet is an investment in the future, as customers can rely on a car that will not depreciate when the Euro5 legislation comes into force, nor will it be hampered by the traffic-limitation measures adopted in many towns and cities.  Finally, the 1.6 Multijet will come with a special package that enables CO2 of less than 120 g per km, thanks to specific measures to optimise the aerodynamics, reduce resistance and limit consumption.

Improved acoustic comfort

The car’s designers have taken particular care to optimise the Bravo’s already excellent soundproofing system with the aim of making the 1.6 Multijet the leader of its category in terms of noise reduction. Compared to the Bravo 1.9 Multijet, the noise value for the 1.6 Multijet engine has been improved by 5% at a speed of 130 kph - more than acceptable even at higher speeds. This is thanks to the engine shields, optimised to absorb the more perceptible frequencies, thicker windows and the use of a high-insulation windscreen.

Reliable gearbox with great credentials

The transmission combined with the 1.6 Multijet engine is the C530, part of the high-end range of gearboxes produced by Fiat Powertrain Technologies, available in 5 or 6 speeds. Both the 1.6 engines (105 and 120 bhp versions) come with a 6-speed gearbox as standard, unlike many of the other competitors in this category. This reduces engine speed, especially when driving on main roads or motorways, with the double advantage of reducing engine noise in the cockpit and cutting down on “actual” consumption. The 6-speed Dual Logic gearbox will also be introduced on the 120 bhp version before the summer to meet the growing demand for automatic transmissions that enhance driving comfort, especially in urban traffic, while providing further improvements in terms of consumption compared to manual transmissions.

The dual-hose external drive of the C530 ensures precise manoeuvring, low noise levels, and the absence of mechanical vibrations through the gearbox. The new generation controls are technologically advanced, thanks to extensive use of high-performing techno polymers used according to their different resistance, weight and self-lubricating power.

The development of materials, pairings and processes was guided by bench tests carried out in extreme climatic conditions, guaranteeing the product’s strength and reliability. The new controls have also been designed to provide total comfort and manoeuvrability. Great care was also taken at the assembly stage, with pre-testing of each component and electronic measurement of all the values that define efficiency, elasticity and tolerance.

The C530 gearbox is configured with two cascade shafts with a differential, and offers excellent manoeuvrability and silent functioning. There is Borg-Warner free-ring synchronisation on all gears – including reverse. Triple-cone synchronisers have been used on the first and second speeds, requiring very limited engagement effort, while single-cone synchronisers have been used for the third, fourth, fifth and sixth gears. Meanwhile, HCR (High Contact Ratio) gear teeth have been used on all gears, while the castings (transmission box – engine/transmission mounts) have been optimised for lightness and noise absorption thanks to the use of F.E.M. (Finite Element Method) calculation techniques. The layout of the gear controls with 4 levels of selection also features a syringe device on the knob of the gear lever to prevent reverse gear from being engaged accidentally. Finally, the hydraulic clutch control integrated into the transmission with a CSC device reduces engagement effort, while the dynamic lubrication reduces wear and provides highly efficient torque transmission and manoeuvrability even at low temperatures.

Quality comes from state of the art factories

To produce a quality car and state of the art engines, you need factories with the very best in methodology, production capacity and human resources. This is why the Fiat Bravo, the 1.6 Multijet engine and the C530 gearbox are all produced in internationally-renowned sites with the best in technology and organizational capability in terms of process and production techniques.

The plant at Piedimonte S. Germano (Frosinone), home of the Bravo, is a centre of excellence in the world automotive industry. Established in 1972, the plant now employs around 4000 staff, producing over 230,000 vehicles each year at a rate of 1000 per day. This is where Fiat has decided to invest, to offer technological and qualitative support to the new model. A new production model has been designed especially for the Bravo, based on a balanced mix of advanced automation and human intervention to ensure complete quality control. The factory also boasts important international certifications (ISO 9001 and ISO 14001). Since 2007, coinciding with production of the Bravo, it has also been working hard on the World Class Manufacturing project with the aim of obtaining WCM certification during 2008.

The same high standards can be found at the two industrial plants which produce the 1.6 Multijet and the C530 gearbox, both produced by FPT – Fiat Powertrain Technologies. The new 1.6 diesel Multijet is produced at the FMA plant at Pratola Serra, which currently employs around 1700 workers with an average age of 33. Opened in 1993, the site has a production capacity of 600,000 vehicles per annum, and manufactures both petrol (1.6 16v, 1.8 16v, 2.0 16v, 2.0 20v, 2.4 20v) and diesel engines (1.9 8v JTD, 1.9 16v JTD, 2.4 20v JTD and recently the 1.9 16v 180hp TST). The Pratola Serra plant can also lay claim to major international certifications including the ISO 9002, ISO 14001 and ISO TS 16949, but most importantly the Excellence in Consistent TPM Commitment 1st Category – recognition which is much sought-after in the field of preventive maintenance, which certifies the level of excellence of the plant and its products.

The C530 gearbox is produced at the FPT plant in Verrone, one of the most advanced mechanical factories anywhere in Europe. Production began in 1974, and the plant now employs 530 people. The plant not only has ISO 14001 and ISO TS 16949 certification, but has also received the Advanced Special Award from the JIPM (Japan Institute of Plant Maintenance) back in 2005, and is preparing for World Class Manufacturing certification, scheduled for 2008.

Fiat Bravo 1.6 Multijet 16v - Technical Specifications