The oil circuit had to be adapted to the specific needs of the engine because of the higher thermal loading. In addition to the conventional pressurized lubrication system, oil lines with upwards directed jets are mounted in the crankcase at each cylinder to provide additional cooling of the piston bottoms. A lubrication circuit was also added for the turbocharger bearings. Both features are shown schematically in Figure 21. The oil from the turbocharger bearings flows back into the oil pan via a flexible tube. The oil pump capacity has been increased by approximately 15 % by an increase in the width of the pump gear from 26 to 30 mm. Before entering the oil fitter the oil flows through a heat exchanger, which is cooled by the engine coolant. Figure 22 shows the cooling of the piston bottom. This special oil cooling lowers critical piston temperatures by approximately 30 C.