Hi speedy,
Warming up of the engine would mean warming up of the engine oil. I
agree with dh on that point.
There is an optimum working temperature for the oil and this would
definitely be part of the engine warming factor.
With the optimum working temperature, the engine oil will serve to
lubricate your engine parts more efficiently rather than from the
cold start stage.
There may be other areas that need to be warm up. But with
technology nowadays, engine are built with very good tolerances,
perhaps the wearable parts , like seals and bearings, would not be
damaged, if the tolerances are within controlled, when running the
engine without proper warming up.
You may not notice the effects immediately, but the stresses built
over prolong exertion of poor lubricated engine parts can lead to
premature failure of the wearable parts and even to the engine
itself.
Warming up may not be limited to the engine exclusively, but being
just a car enthusiast, my knowledge is not quite as far reach as an
automotive builder.
To sidetrack from the topic,
You may wish to read on this useful link.
http://www.virginiaengines.com/maintenance.htm
It contains useful information for car owners.
Have a good day.
Cheers
