New smart fortwo cdi revealed

Posted on 06/06/2007 under: Hatchbacks, SMART

With fuel consumption of just 3.3 litres per 100 kilometres (NEDC) and emissions of 88 grams of carbon dioxide per kilometre the new smart fortwo cdi is the most economical production car worldwide. A full tank of fuel costs around €38.00 (assuming a litre price of €1.15) and 33 litres of fuel will take the 33 kW/45 bhp two-door car approximately 1,000 kilometres – for example theoretically from central Berlin to the outskirts of Paris without refuelling.

The smart engineers have improved the successful cdi engine from the predecessor model and equipped it for the future. The power and torque have each increased by ten percent, whilst the fuel consumption has decreased by around 13 percent. In figures this means power of 33 kW/45 bhp and maximum torque of 110 metres that is delivered between 2,000 and 2,500 rpm. The new smart fortwo cdi thus offers a combination of agility, economy and environmental compatibility that is unique in this class and that adds up to all-round driving fun.

This is thanks to the world's smallest direct-injection diesel engine – a masterpiece of engine development – that boasts technology previously only found in larger capacity engines, despite its extremely compact dimensions. For example the latest generation common-rail direct injection which builds up high injection pressure of up to 1,600 bar (previously: 1,350 bar) even at low revs, and injects the fuel into the combustion chambers with newly developed six-hole injectors, enabling an even more efficient combustion process.

A turbo-charger, charge-air cooling, electrically controlled and cooled exhaust gas recirculation, hydraulic compensation of valve clearance and a state-of-the-art light alloy construction are further features that identify the cdi engine as a high-tech package.

The smallest direct-injection diesel engine with state-of-the-art technology

The three-cylinder engine has also adopted two-phase fuel injection from the CDI engines of its sister brand Mercedes-Benz. A few milliseconds before the main injection a small quantity of diesel is injected into the combustion chambers where it ignites and preheats the cylinders. This results in a noticeably quieter combustion noise level than an engine without this pilot injection. The electronic "brain" of the cdi engine – a high-performance micro-computer that controls the whole engine-transmission system – calculates how much fuel is needed and the interval at which pilot injection and main injection take place.

Source: DaimlerChrysler