Engine brake systems are based on the concept of spending a large amount of the vehicle’s kinetic energy by releasing pressure from the cylinder.Although an important part of the kinetic energy is used during compression, unless the spring effect of gases is suppressed, a good portion of it is returned to the wheel during the power stroke.This goal can be achieved by releasing of compression just before maximum cylinder pressure is reached.The present paper illustrates investigations upon the exhaust valve opening and closing angles that determine a braking event and their influence upon engine torque.
