Is there any scientific basis for the 2500rpm number that has been posted a number of times? Just to be clear we are running modern engines, with modern synthetic oils (hopefully)... I can see no logical or scientific reason to stay under 2500 RPM. If the system has oil pressure, then there should be no metal to metal contact. Certainly full throttle or Red line ops are a no-no until the fluids are warm, because that may generate oil pressures that are higher than factory parameters. Also, in extreme temps, dissimilar metals contract and expand at different rates. Metal to Metal interference form this phenomenon is highly unlikely, but is still something that we should keep in mind.
2500, 3000, Idle...whatever. The factory says 4K is the limit cold and there is likely some scientific reason for that...other than someone on an internet forum said it once and 25 people repeated it.
