Cylinder Heads
| ITEM | DESCRIPTION |
|---|---|
| 1 | Cylinder head |
| 2 | Exhaust camshaft |
| 3 | Intake camshaft |
| 4 | Cylinder head intake port |
| 5 | Fuel injector location |
| 6 | Exhaust valves |
| 7 | Cylinder head exhaust port |
| 8 | Spark plug location |
| 9 | Intake valves |
The cylinder heads are manufactured in gravity die-cast aluminum alloy and are unique for each cylinder bank. Deep-seated bolts reduce distortion and secure the cylinder heads to the cylinder block.
Each cylinder has 2 inlet and 2 outlet valves. To help achieve the required gas-flow characteristics, these are arranged asymmetrically around the cylinder bore. Each cylinder has a centrally mounted fuel injector and spark plug.
The threads for the spark plugs are machined at a precise start point to provide that each spark plug is orientated in the cylinder correctly. The benefits of this are optimum spark plug intrusion into the combustion chamber to improve combustion, idle stability, dilution tolerance and spark plug durability. The spark plug must be tightened to the specified torque to provide the correct orientation.
The cylinder head gasket is of a multilayer construction.