The ticking noise could be from one lifter if the noise is coming from the valve cover , sometimes over time a piece do sluge or some crud gets into them and they will bleed down and tick away until the oil pumps them up to take up the slack and the tick goes away , one you can remove them one by one and take them apart to clean the little check valve in them , do not mix up the parts , clean with a spray can of B-12 chem tool when you pull them apart , keep every thing clean when you have it apart , done this a few times on high mileage pintos that lacked needed oil changes , hope this helps

Quite often an exhaust leak at the manifold will make a ticking noise until it heats up. Does the noise increase when the engine load is more?
mike