This week across Italy the Fiat Bravo version equipped with the exciting and innovative brand new 150 bhp 1.4 T-Jet engine went on sale, its arrival in Fiat's domestic market following closely on from the UK which recently began taking orders for the T-Jet unit to coincide with the C-segment car's launch. Available in Italy in the higher equipped versions of the Dynamic, Emotion and Sport packages, the new engine version has a price list of 20,280 euros and standard equipment includes the sophisticated ESP system and Hill Holder.

Through cubic capacity downsizing allied to the adoption of the smallest possible turbocharger, Fiat’s responsive new 150 bhp 1.4 litre T-Jet engine combines performance equal to or better than a conventionally aspirated 1.8/2.0 litre petrol engine, but with a reduction of between 10 percent and 20 percent in fuel consumption and emissions. These advantages are especially useful, given the importance of the fleet market, where taxation plays a major role. A 120 bhp version of this new unit, with performance equal to or better than a conventionally aspirated 1.6 litre petrol engine, will be added to the range in due course.

The arrival of the new 150 bhp T-Jet engine has increased the range of a model that is already experiencing a great public success, verified by over 55,000 orders since its launch (end of January 2007) up to 30th of June, with over 50 percent of these coming outside Italy. In Italy from April up to date the Fiat Bravo is the leader of its segment with an average share of almost 17 percent of the market. The mix of sales composition is biggest in the highest versions available: 35 percent of customers have chosen the top of the range versions (Emotion and Sport) while 60 percent have gone for the Dynamic version; the preferred engine, by 70 percent of customers is the 1.9 Multijet with 120 bhp.

T-Jet

The new 1.4 T-Jet is the first one of a new family of engines. The 120 bhp and 150 bhp 1.4 litre 16 valve T-Jet engines are the first examples of a new family of turbocharged petrol units developed by Fiat Powertrain Technologies to combine the sporting performance and low NVH characteristics of a petrol engine with fuel economy comparable to a diesel unit and CO2 emission levels which readily comply with increasingly stringent European regulation. Through cubic capacity downsizing allied to the adoption of the smallest possible turbocharger, Fiat’s responsive new 120 bhp and 150 bhp 1.4 litre T-Jet engines combine a performance equal to or better than a conventionally aspirated 1.6/1.8/2.0 litre engine.
 

This is achieved along with a reduction of between 10 percent and 20 percent in fuel consumption and emissions. Employing state-of-the-art computer aided design and calculation systems to simulate unit stress under turbocharging, every aspect of the 1.4 litre powerplant has been re-evaluated. Three-dimensional computational fluid-dynamics studies of the entire thermodynamic cycle, injection phase and the engine cooling circuit, as well as thermo-mechanical analysis of cylinder head, block and piston stress resulted in comprehensive redevelopment of the combustion system, intake and exhaust manifolds, cam profiles and phasing, intake system, engine coolant circulation and spark plugs.

The new T-Jet engines feature optimised intake port and manifold design; a revised injection system and bespoke spark plug design to improve knock resistance and pre-ignition; a reduction in both inlet and exhaust valve lift time to optimise air mass flow; a reduction in compression ratio from 11:1 to 9.8:1; piston, con-rod and crankshaft redesign; a new, reduced volume exhaust manifold for maximum exploitation of the exhaust pulse energy, and improved engine cooling efficiency through a revised coolant path and a redesigned water pump impeller.

Excellent combustion characteristics have allowed for the adoption of a notably small turbocharger. With a turbine diameter of only 33 mm, this highly compact and responsive turbine is located directly above the exhaust manifold, with the attendant catalytic converter close-coupled to the turbine exit.

Via a ‘drive-by-wire’ throttle system, the new 1.4 litre T-Jet engines provide outstanding low-end torque, almost entirely devoid of the lag in power delivery traditionally associated with turbocharger installations. The 150 bhp T-Jet engine offers identical torque delivery at 1750 rpm but, via an ‘overboost’ button located on the centre console in Sport versions, will deliver an impressive 170 lb ft at 3000 rpm, endowing the Bravo with a 0-62 mph acceleration time of 8.2 seconds and a top speed of 131 mph. Notwithstanding such lively performance, this superbly responsive powerplant will still return nearly 40 mpg in the combined cycle and restrict CO2 emissions to just 167 g/km.