Cam and lifter problem

I have heard acout soem of the XE268s being "noisey" like that. I've installed a bunch of XE grinds big and small. The XEs larger than the 268 can be a little noisey at idle, but they call for the anti pump up lifters, which can be noisey. (IE Rhodes lifters). If it hasnt eaten the cam, and you are certain the preload is fine and not changing, then I would not sweat it. I also tend to think all roller rockers are noisey at idle. Sometimes made worse by the style of valve cover used. If it's indeed ticking, use a long extension as a stethoscope to figure out what it is. Cup the female end with your hand with the extension being the 'outside" end, and your ear being the "inside end". Then place the male end against the head, or block, or valve cover with the engine running. You will hear the tick...