[DAVID GAGNARD]

Solid roller cams will tick or be "noisy" under the hood, if your motor has a hydraulic roller cam, there should be no ticking or noise per se on the top end of the motor, unless there is a very loose rocker arm. If the rocker arm was not adjusted correctly or has lost it's adjustment, then it may have "clearance" between the roller tip and the valve, which it should not........

With the engine idling and the ticking noise going on, you should be able to at least determine which side of the motor it's coming from and start from there......

My bet is on an exhaust leak,either the header itself or the gasket....

David