I don't see how a cam bearing could "tick". They can (and do) affect oil pressure, but there's too many support points for them to be contributing to a "tick" noise unless it's end play. IME there's a distinct difference between what I call a "tick" compared to a "knock". Lifter's "tick", while rod bearings "knock" and mains "clatter" or "chatter". If the PCV was removed then it must have breathers to relieve crank case pressure, right? Does your "tick" remain consistent, and follow rpm, diminishing as rpm gets up into mid-range?