[thstone]

For reference, the Boxster engine uses hydraulic lifters between the overhead camshaft and the valve. Not likely that a lifter would be quiet at cold and noisy at warm temps.

So my first guess is that the ticking is something other than a lifter, like the water pump or another engine accessory like the alternator bearing, power steering pump, a/c bearing, etc.

I'd remove the front engine cover (inside the car) and spend some time with an automotive stethoscope to better isolate the location of the tick.