88 million pounds and 46 mths later enter the new GDi engine from Kia.
Putting the Kia & Hyundai brands at the cutting edge of engine design and management the GDi needed to achieve three seemly incompatible goals: lower emissions while raising power output and improving fuel economy.
Based on the new Theta II family of units, the first engine to go to market is the 2.4 litre four cylinder unit with a compression ratio of 11.3:1, delivering 201ps at 6300rpm and 25.5kg.m of torque at 4250rpm in its initial Korean domestic market specification.
It’s likely that the new 2010 Sorento & Santa Fe from Hyundai will get these engines when full production gets underway by the end of 2010.
GDI explained
One serious limitation of conventional fuel injection systems is that as engine revolutions increase, the valve opening and closing times get progressively shorter, thus reducing the time available to inject fuel. GDI avoids this problem altogether by positioning the fuel injector in the most optimal location, directly inside the combustion chamber to offer unparalleled precision. With this shorter and more direct path, far greater control is attained over the combustion process: A high pressure fuel pump injects the fuel at pressures of up to 150 bar, in precise amounts and intervals.
The injection is split into two phases to achieve optimum combustion: in the first phase, the pilot injection and ignition trigger the piston’s downward power stroke. Then, in the main injection phase, during the piston’s descent, more fuel is injected and is ignited.
This split-injection technique reduces loading on the catalytic converter and helps lower emissions. This is particularly beneficial during cold starts when emissions are highest because the catalyst has not reached its optimal operating temperature. Split-injection enables the catalytic converter to reach the optimal operating temperature faster thus reducing emissions by 25 percent during cold starts and meet’s California Air Resources Board’s ULEV-2 and PZEV standards.