5.2 magnum options

i cant tell which cylinders are missing, I have tried the carb cleaner on the intake ( no change ) I also tried the water mist on all the wires ( no change ) the cam was in the engine when I got it ( so I ran it, its a Comp computer cam ) I have tried pulling a wire at a time but can never identify any one cylinder worse than any other.
I tried moving the timing light from wire to wire, it is almost like they all miss on occasion.
that is part of the reason I switched plugs, wires, distributors and even the carb chasing
this miss.