Hyundai has unveiled its first seven-speed dual-clutch automatic transmission at the Paris motor show 2014. The manufacturer says the new gearbox provides "an improvement in fuel consumption and CO2 emission compared to a conventional six-gear automatic transmission, while acceleration performance also improves".
The 7DCT consists of two dry clutches and an actuator for each clutch, with engine power transferred independently into the odd and even gear train, ensuring it is ready to shift into the next gear without any torque interruption. For optimised responsiveness, the electric motor-driven actuator is applied, while the external damper keeps NVH (noise vibration harshness) levels under control during driving.
Hyundai has also displayed two new turbocharged petrol direct-injected (T-GDI) engines, including a 1.0-litre three-cylinder unit that will be installed in the new i20 overseas.
The engines are 1.0-litre and 1.4-litre units which are part of a new generation of engines from the Korean company's Kappa family. The smaller unit is a 998cc three-cylinder that's based on Hyundai's existing Kappa 1.0 litre MPI engine, albeit with various enhancements and new technologies, including direct petrol injection and a small, single-scroll turbocharger. It can be tuned to produce up to 118bhp and 17.5kgm of torque.
The new engine comes with an electronically controlled wastegate to optimise flow and improve low-end torque and throttle response. It features a six-hole GDI injector, pressured to a higher-than-average 200 bar, securing a clean combustion and improving fuel economy and emissions. It uses a split-cooling concept to manage different temperatures in the cylinder head and block area, cutting warm-up times and improving efficiency. To keep the engine unit as small as possible, the exhaust manifold is integrated within the cylinder head.
The second new engine is the Kappa 1.4-litre T-GDI unit, which is the successor to the Gamma 1.4-litre engine. At 87kg, the engine's base weight is 14kg less that the old motor, and the unit is also more compact. It incorporates a high-pressure single-scroll turbocharger integrated within the exhaust manifold. This improves throttle response time and low-end torque. The new design injects fuel directly inside the cylinder, improving combustion rates for better power and fuel efficiency. It can be tuned to develop 115bhp and maximum torque of 21kgm of torque.
First Published: Oct 08, 2014 12:38 IST