-     Change of Valve Timing
By turning the camshaft, the exhaust valve is opened in the area of the upper dead center causing the compressed air to flows directly into the exhaust manifold. No work is done on the engine during the expansion of the compressed air. It evaporates in the exhaust pipe. The braking power can be controlled by varying the exhaust timing.
The engine brake is a cost-efficient solution and in addition can be varied over the transmission ratio (however, limited to the admissible engine speed range!).