Volvo’s new engines promise more power with less fuel
Motoring Staff
2010-08-31
Volvo will be launching two new four-cylinder 1.6-litre petrol engines, T3 and T4, which will feature the very latest direct injection technology.
The GTDi (Gasoline Turbocharged Direct Injection) concept was primarily developed to offer improved fuel consumption without compromising on performance. Therefore the 1.6 GTDi T3 features 110kW while the T4 offers 132kW and both will be available in the all-new Volvo S60 and V60 in late 2010.
The 134kW T4 engine delivers an estimated torque of 240 Nm from just 1600 rpm all the way up to 5000 rpm. An automatic on-demand overboost function provides around 270 Nm of torque which results in econsiderable pulling power across the entire rev range, whereas the 110kW T3 version offers around 240Nm of torque. Yet, Volvo claims the torque curve is relatively gentle, providing a comfortable driving experience.
On both 1.6-litre engines, each injector has been positioned centrally above the piston, just beside the spark plug. Each injector has six holes, which offer finely atomised fuel distribution. These centrally located multi-hole injectors make it possible to control fuel dosages precisely. In cold starts, the fuel is sprayed into the middle of the combustion chamber just prior to ignition.
This helps cut emissions and considerably reduces the amount of fuel consumed. Another effect is a major reduction in the amount of soot particulates compared with a side-positioned injector.
Direct injection gives a high fill rate in the combustion chamber. Apart from effective combustion and lower emissions, this also helps the turbo start up earlier and provides swift response even from low engine revs. Hence promoting fast acceleration and good drivability at low speeds.
The combination of direct injection and turbocharging coupled with variable valve timing has made it possible to deliver performance properties on a par with far larger engines, whilst reducing fuel consumption and environmental impact to considerably lower levels.
Volvo estimated reductions in fuel consumption and exhaust emissions in the region of twenty percent compared with a conventional petrol engine with larger displacement and similar performance.
Both engines will also feature DRIVe fuel-saving technology:The six-speed twin-clutch Powershift transmission combines the manual gearbox's efficiency and driving dynamics with the automatic transmission's smoothness and convenience. Clutch operation is also coordinated so that no torque losses arise during gearchanges. The result is the same comfort and seamless drive as a conventional automatic transmission, combined with the performance of a manual gearbox.
