Systems and methods for hydraulic and/or variable valve actuation of
engine valves are disclosed. An embodiment of the present invention may
include a hydraulic valve actuation system operatively connected to an
engine valve. First and second control valves may be operatively
connected to the hydraulic valve actuation system and adapted to
selectively release hydraulic fluid from the hydraulic valve actuation
system independent of one another. The first control valve is preferably
a solenoid actuated trigger valve and the second control valve is
preferably a mechanically or hydraulically actuated valve.