New diesel fits all

A new 1.4- litre common rail diesel engine is the first result of a co-operative agreement signed between PSA and Ford on September 29, 1998.

A new 1.4- litre common rail diesel engine, marketed as the HDi 1.4l by PSA Peugeot Citroën and the Duratorq TDCi 1.4 by the Ford Motor Company, is the first result of an agreement that the two companies signed on September 29, 1998. The agreement covers the joint design and production of four families of common rail direct injection diesel engines: 1.4- and 1.6-litre engines, a second-generation 2-litre engine, a 2.7-litre V6 engine and a new family of engines for light commercial vehicles.

In the 18-month period following the launch, a total of 23 applications will be introduced for this new family of engines for use in both partners’ vehicles. To achieve this goal, the project team had to devise an engine architecture that could be easily adapted to various types of vehicle based on a ‘plug & play’ design and production concept.

This involved developing common engine-vehicle interfaces for different vehicles. For example, the air, water and fuel supply components, as well as the electrical and mechanical connections, are the same regardless of the host vehicle and engine version installed.

All engines in the family have the same core (cylinder block, crankcase, connecting rod, bearings, oil pump, water pump, etc.).

In addition, the project team developed uniform modular designs for sub-assemblies. For example, the intake system consists of a single multi-function unit that includes the air cleaner, airflow meter, turbocharger muffler, air intake manifold, exhaust gas treatment system, cylinder head cover and diesel fuel filter. The same approach was applied to the water and fuel supply components, and to the electrical and mechanical connections.

The HDi 1.4 and Duratorq TDCi 1.4 engines will offer power outputs ranging from 60 to 92 hp, and torque levels from 150 to 200 Nm.

With these new engines, both partners’ small cars will feature an average fuel consumption of between 3.4 liters per 100 km (90 g CO2/km) and 4.1 litres per 100 km (110 g CO2 /km), as measured for the MVEG European urban and highway driving cycle. Lower medium segment vehicles will achieve 4.5 liters per 100 km with CO2 emissions of 120 g / km.

Weighing in at a total of 98 kg, the new engine is 50 kg lighter than a 1.9-litre pre-chamber engine, the most comparable equivalent in terms of performance. This was achieved through extensive use of aluminum alloys and composite materials.

The cylinder block and cover are made of pressure-cast aluminum, with cast-iron bearings and sleeves inserted during the casting process. Also made of aluminum, the cylinder head consists of a lower gravity-cast section and an upper section that supports the pressure-cast camshaft.

The camshaft consists of sintered cams that are force-fit onto the shaft. This design reduces the weight of the assembly by 1.3 kg or 30%.

Other components such as the turbocharger muffler, air intake manifold, exhaust gas treatment system and cylinder head cover are made entirely of composite materials. The same technology is used for key components in the water circulation system, including the water pump cover, the water inlet and outlet housings, and the oil pump strainer.

All moving parts have been designed to reduce their size and weight. For example, the valve stems are 5.5 mm in diameter, a size that is more common in small high-performance gasoline engines or motorcycle engines.

Another factor in lowering fuel consumption is the reduction of friction losses. The use of roller-type valve rockers helps reduce fuel consumption by 1.5 to 2%, depending on engine speed.

Two types of turbocharger are offered with the engines: a fixed-geometry turbocharger for 8-valve engines, and a variable-geometry turbocharger for 16-valve engines. The variable-geometry turbocharger leverages adaptive control technology to optimise throttle response.

These turbochargers achieve rotation speeds of 280,000 revolutions per minute.

To improve the performance of the engines further, the combustion gas treatment systems have been located as close as possible to the turbocharger to take advantage of the highest exhaust temperatures. Accordingly, the cross-flow design of the 8- and 16-valve cylinder heads enables the exhaust to be positioned towards the front of the engine.

The injectors have six orifices, each with a diameter of 118 microns, i.e. equivalent to the thickness of a single hair. They enable an even finer spray of diesel fuel, which ensures an extremely uniform fuel-air mixture.

Motor vehicles with these engines will have low CO2 emissions, ranging from 90 to 120 grams per kilometre depending on the model, compared with an average of 171 grams for new vehicles sold in Europe in 2000.

The 1.4-litre common rail diesel engine will be manufactured at the PSA Peugeot Citroën plant at Douvrin, France. A new production facility has been built at this location to produce engines for both PSA Peugeot Citroën and Ford.