Two of the world’s biggest car companies are claiming an industry first by using compacted graphite iron (CGI) to build a new ‘flagship’ turbocharged diesel engine.
According to Ford and PSA Peugeot-Citroen, the use of CGI for the engine block rather than conventional cast iron is a landmark in volume engine production.
The two companies said the new 2.7 litre V6 engine, which will make its debut next year in the Jaguar S-Type, is the most significant result yet of an earlier deal to share design and production of common-rail, direct-injection diesel units.
The strength of CGI means that less material is needed than for a conventional cast iron block, allowing the engine to come in at a relatively lightweight 202kg and take up less space. This boosts its power-to-weight ratio and fuel economy characteristics.
The use of CGI has required advances in manufacturing processes, including the development of machine tools to handle the material.
The engines will be made at Ford’s new Dagenham diesel facility, which will include the first high-volume production line to machine and produce CGI engine blocks.
The new unit is the first six-cylinder engine developed via the Ford/PSA co-operation pact and is aimed at the rapidly growing premium end of the diesel market, where customers are reluctant to compromise in areas such as performance, noise and efficiency.
The partners hope the V6 will allow them to compete with rivals such as BMW and Mercedes, both of which have diesel engines designed for larger cars. After initial use in the Jaguar, the engine will appear in other premium models across the two companies’ ranges.
Alongside the use of CGI, the engine includes a host of technical innovations developed by Ford and PSA during their five-year collaboration.
The V6 boasts a compression ratio of 17.3:1, low for a diesel engine. This helps improve the quality of emissions and leads to quieter combustion. The engine also employs common-rail fuel injection technology capable of achieving an operating pressure of 1,650 bar, which is higher than previous systems.
The quantity of fuel injected is controlled by a piezo actuator, while the injectors themselves deliver fuel from a hole 145 microns in diameter, providing a spray of fuel fine enough to achieve maximum uniformity of fuel/air mixture.
Alongside these developments Ford and PSA have come up with an advanced electronic control unit (ECU) to monitor and manage the new engine. The ECU draws data from 23 sensors and sends out instructions to 20 actuators.
Ford and PSA have spent £230m on the joint diesel programme. Other engines developed will be used in smaller car brands produced by the two companies.