New developments in engine management technologies will fuel the drive towards automobiles that emit less, are more powerful and efficient Fuel costs are rising and emissions restrictions are getting tighter the world over. Automakers are required to comply, but with- out sacrificing performance or raising prices to put themselves at a competitive disadvantage. At the core of the stiff challenges faced by automakers are engine management technologies. These include various critical areas of a powertrain. Areas that are often described as variable valve timing, cylinder deactivation and direct injection. These are further linked to elements like the engine's electronic fuel management system, exhaust gas recirculation system and more. While many analysts and experts expect the diesel engine to turn into a popular choice in the years to come, and at least until new revolutionary alternate fuel technologies firm up, the travel into future is bound to see remarkable developments in diesel engine technologies. At the forefront currently is the common-rail (CR) diesel engine management technology. Volkswagen is turning to the CR technology after experimenting with direct injection diesel technology for almost a decade. Considered superior to most other diesel technologies around at present, the CR diesel engine technology employs a high pressure rail that connects with the high pressure diesel pump at one end and the respective injectors at the other end. Developing pressures in the region of 1400 bar to 2000 bar, the rail supplies each computer-controlled injector containing a precision-machined nozzle and a plunger driven by a solenoid or piezoelectric actuator. The fact that each injector can be controlled electronically, a CR diesel engine can be engineered to have multiple injection cycles within a fraction of a second. This provides significant advantage over direct injection diesel engine, which proves to be noisier and therefore less refined. Pilot injection or a set of injections in CR engines reduces noise as well as the amount of pulsation that could lead to a certain coarseness of operation. Presenting driveability akin to a conventional fuel injected petrol engine, the CR diesel engine produces healthy torque at low engine revolutions. Aiding the performance is the turbocharger; the development of piezo injectors enabling an even more precise control of injection cycles. The effect of which is more power, better efficiency and lower emissions. Consider the multijet diesel engine technology from Fiat, which won the engine of the year award in Europe. Powering a plethora of small and mid-size cars, prompting Fiat to announce that Fiat Diesel drives India, the multijet technology is actually a glorified form of CR diesel injection technology. Like explained earlier, these engines work the way any CR engine would. The series of injections starting with the pilot injection are termed as multijet! Developed in association with Robert Bosch, the multijet technology (also termed as jet turbo diesel) was first seen on Alfa Romeo cars. Over a period of time, and with new developments, the technology found its way into other Fiat group cars. Today, Fiat manufactures the smallest Multijet engine in its family Ã¢â‚¬â€œ the 1.3 Ã¢â‚¬â€œ at its plant near Pune for employment in Fiat and Tata range of automobiles. In its second generation, the multijet engine of current day has up to seven injections leading up to the main injection, electronically managed in response to the driver demand, and leading to smoother and livelier operation. Aiding the process are new turbo charging technologies like twin stage turbo and variable geometry turbo. Even as Volkswagen continues to move away from direct injection turbo-diesel engine technology to CR diesel engine technology, at the petrol end of the spectrum, it is promoting the gasoline direct injection (GDI) technology aggressively. Where a conventional multi-point petrol fuel injection engine develops pressure of up to 4 bar, a GDI engines does 200 bar as of current. Newer developments are however showing signs of injection pressures pushing up to 1600 bar! Having multiple advantages that make it very attractive under both current and projected market conditions, the future of GDI technology points in the direction of homogeneous or stoichiometric operation. Take a look at the CGI engine technology Mercedes Benz introduced in India recently. Drawing inspiration from CGI technology introduced on the Mercedes 300SL Gullwing, the CGI technology uses spray guided direct injection with piezo injectors. Microsecond response times of the piezoelectric injectors provide the basis for delivering multiple injections per power stroke, and thus for lean burn operation. Displaying better thermal efficiency than port injection engines, the CGI technology results in more power, better efficiency and lower emissions. This helps reduce the spending on exhaust emission technologies. Going a step further, the beauty of CGI technology rests in the fact (and from the emissions point of view) that the engine operates with a high compression ratio and high excess air. The fuel is injected into the air compressed by the pistons at a relatively late stage. Such lean-burn operation was previously only possible in the lower load ranges. Thanks to the new, spray-guided combustion system, Mercedes engineers have now been able to extend this lean-burn operating mode to higher RPM and load ranges, achieving further reductions in fuel consumption. For example, the V6 engine in the CLS 350 CGI still operates with stratified charging at speeds of over 120 km/hr, only later switching to homogenous operation where the fuel/air ratio is 1:14.6 (lambda = 1). For India, Mercedes Benz has chosen to go the homogenous way. For lean-burn, the engine will need to be fed with low sulphur diet. A new powertrain technology, again from Fiat, which is just emerging, is MultiAir. The innovative MultiAir system controls the air in controlled-ignition petrol engines without the usual throttle valve, and therefore with a greater degree of flexibility than mechanical timing systems. This electrohydraulic valve activation technology is based on the insertion, between the camshaft and the engine inlet valve, of an amount of oil (high pressure chamber) that can be varied by a valve, which in turn is controlled by a specific electronic control unit. This allows the opening profile of the valve to be modified in response to the request for air from the engine and to the running speed. Different strategies can be employed (Early Inlet Valve Closing Ã¢â‚¬â€œ EIVC, Late Inlet Valve Opening Ã¢â‚¬â€œ LIVO, or Multi-Lift) to optimise combustion efficiency, with considerable benefits in terms of power output, torque, consumption and emissions. Another advantage of this system is the fact that the air pressure upstream of the valves is always constant. This characteristic allows the torque response of the engine to be increased without any delay, on both an aspirated and a turbocharged engine, increasing the 'fun to drive' factor.Variable cam timing systems have been around for a while. If the MultiAir system brings a breath of fresh air to the scene, the I-VTEC system from Honda and the VVTi system from Toyota are quite familiar. Even the CGI technology of Mercedes Benz uses a variable valve train system, which complements the GDI and twin stage turbo. The CGI engine is therefore a burning example of current advances in engine management technology. It is also an indication of what is expected to come in the near future. At least as far as the internal combustion engines are concerned.