Technical Description
Technical Description
The new 3.0 l V6 supercharged engine with direct fuel injection installed in the Cayenne S Hybrid guarantees maximum efficiency of the hybrid drive in conjunction with an electric machine. In addition to ensuring typical Porsche driving characteristics with V8 performance, the main development goal was to achieve low fuel consumption, reduced CO2 emissions and compliance with all worldwide emission standards.
Porsche is using a supercharged V6 engine for the first time. The engine produces 333 hp (245 kW) at 5,500 rpm to 6,500 rpm and delivers a maximum torque of 440 Nm in the range between 3,000 rpm and 5,250 rpm.
Cayenne S Hybrid 3,0 TFSI Engine data
Cylinder spacing 90 mm
Cylinder bank offset 18.5 mm
Main bearing diameter 65 mm
Con-rod bearing diameter 56 mm
Con-rod length 153 mm
Block height 228 mm
Displacement 2995 cm3
Stroke 89 mm
Bore 84.5 mm
Compression ratio 10.5:1
Max. power at engine rpm 3 hp (245 kW) at 5,500 to 6,500 rpm
Max. torque at engine rpm 440 Nm 3,000 to 5,250 rpm
Characteristics
The most important characteristics of the new 3.0 l V6 supercharged engine include:
- Cylinder bank angle 90°
- Wet-sump lubrication
- Supercharger
- Charge-air cooling
- Fuel consumption measures on intake side
- Aluminum cylinder head
- Solid aluminum engine block
- Four-valve technology
- Continuous camshaft adjustment
The engine is a 6-cylinder, 24-valve gasoline engine with a cylinder bank angle of 90 degrees and two camshafts per cylinder bank. The 3.0 l V6 engine consists of an aluminum engine block, an aluminum cylinder head and other state-of-the-art technological features such as thermal management and a regulated oil pump.
The oil supply system is based on the principle of wet-sump lubrication, which safeguards the functions of the engine in dynamic driving mode and on slopes or steep uphill climbs when driving off-road, for example. In contrast to previous turbocharged engines used in Porsche models, turbocharging on the new unit is achieved using a supercharger with charge-air cooling. The supercharger with charge-air cooling offers special advantages for the specialized use and characteristics of the full parallel hybrid drive in an SUV. Because the supercharger has a permanent mechanical connection with the crankshaft drive, the boost pressure is available immediately and the mass air flow through it increases continuously together with the speed of the combustion engine. The supercharger is located directly inside the inner V of the engine, which means that the aspirated, compressed air does not have far to travel to the cylinders and consequently the engine offers outstanding response characteristics. The enhanced response of the engine reaps particular benefits at low speeds in an urban driving environment, where the Cayenne S Hybrid is able to demonstrate the positive effect that the Auto Start Stop function, the recovery of brake energy and driving solely under electric power have on fuel consumption. The exhaust gas after-treatment system also benefits because the catalytic converter reaches the perfect operating temperature more quickly.
The supercharger in the Cayenne S Hybrid is a space-saving Roots blower with charge-air cooling and a bypass valve that guarantee the rapid response of the V-engine. Two parallel shafts in the supercharger housing connected via a gear stage are powered by a separate belt drive. The gear stage enables the fully synchronous rotation of the two shafts in opposite directions to one another. Rotors are mounted on both shafts and are sealed on all sides (opposite the blades on the second shaft and the supercharger housing). The two shafts rotating in opposite directions convey the uncompressed air mass from the air inlet, between the rotors into the supercharger and then to the air outlet. (Each rotor is fitted with 4 vanes and positioned at 160 degrees to the longitudinal axis to guarantee a continuous flow of air.) Compression occurs when the mass of air that has accumulated in front of the intake valves is forced inwards. The supercharger is fitted with a charge-air cooler for each cylinder bank with a low-temperature coolant system to enhance the turbocharging effect.
The supercharger is equipped with an integral boost-pressure control because charge air is not required in all operating modes and the continuous increase in boost pressure would result in an excessive accumulation of air and therefore a loss in power. A bypass valve is used instead of a complex boost pressure control that incorporates a magnetic clutch for engaging and disengaging the supercharger. Once the specified or maximum boost pressure is reached, some of the delivered air can be returned back to the intake side by opening the bypass valve.
