Variable Camshaft Profile (Cps), Only Applies To B6324S
| Number | Designation | Number | Designation |
| 1 | Camshaft phase setting | 3 | High lift |
| 2 | Shift lobe | 4 | Low lift |
The ideal engine should have low valve lift for low engine RPM and loads, and high valve lift at high RPM and loads.
To achieve this, an engine with two completely different camshaft profiles is required.
This engine has a patented system for camshaft profile switching. The system uses two completely different cam profiles designed on the same camshaft.
The inlet camshaft is provided with three cams for each valve, one centrally located with small lift height, 3.6 mm, and two equally sized outer cams with big lift height, 10.0 mm. With a small lift height at low load and at engine speeds up to approx. 3000 RPM, the primary benefit is lower fuel consumption.
In principle, during the time that the lift height is small, the air damper is completely open. Control of the incoming air volume to the cylinders takes place through control of the camshaft's opening times. Hereby the pump losses are reduced, which in turn gives lower fuel consumption.
Low lift
At small lift height (4), only the centrally placed cam acts on the valve, which takes place trough the inner valve depressor. The outer cams act on the outer valve depressors, which follow the cams' movement. Since the centrally located valve depressor and the outer depressor are not connected, the outer depressor moves without affecting the valve. Thus, lift height becomes small.
High lift
At high lift height (3), the inner valve depressor is connected with the outer valve depressor with lock pins. The outer camshaft cams' movement is transmitted through the outer valve depressor, on through the lock pins and the inner valve depressor to the valve. Thus, lift height becomes big.
The position of the lock pins is controlled hydraulically with two electro-hydraulic valves. One electro-hydraulic valve controls the valves for cylinders 1, 2 and 4, while the other controls the valve for cylinders 3, 5 and 6. Thus, the electro-hydraulic valves control 6 valves each (as the engine has 2 inlet valves and 2 exhaust valves per cylinder).
The position, on/off, of the electro-hydraulic valves is controlled by the Engine control module (ECM).
The inner valve depressor works like a hydraulic valve depressor, which compensates any wear. Thus the valve clearance is "0".
The exhaust camshaft is conventional and has a lift height of 10.0 mm. The valve depressors are mechanical, that is, they "have" valve clearance.