Cold startup and diving

[VLADDS@domain.elided]

Hi everybody
About the cold start up I'm interested in this:
How would one explain the part where you don't have to rev up, untill it gets
warm.
The part with the temperature of the oil being uneven and the viscosity being
therefore uneven and kinda high is irelevant to the rpm's themselfs.The
critical fricition occurs only at engine startup and the rotational speed of
lubricated parts doesn't seem to me that would at relatively higher rpms
compromise the oil film lubrication properties. Afther all the oil pressure
increases with rpm too, and one would think that this part was carefully
considered at design.
Another thing is also that the load of the engine is not necessarily
proportional with the rpms .Once can gently gradually accelerate to high
rpm's.
I think that probably there are only vibrational problems.I was told once that
the critical spped of engines is not allways designed up and above all
limitated values.
Any info is appreciated..
Not related to the above:
As far as used cars, i have noticed that that those driven in high rpm's
constantly, vibrate less as you climb the scale and those that were kept low
"protest".Have you noticed how on same year and model and miles, the automatic
used car revs a bit easyer (maybe just a subjective observation of mine),
because the automatic has taken the car troughout the rpm spectrum without
holding out

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