[TD in DC]

OK, in light of the air-cooled bias of this board, I realize this is not the best place to ask this question, but here goes.

In every modern Porsche owner's manual that I have read, the manual links "normal operating temperature" to water temperature rather than oil temperature. Also, with each successive manual, there seems to be less discussion about the need to allow a car to warm-up before pushing the motor. IIRC, the 996 owners manual said to keep the rpms below 4K until normal operating temperature had been reached (but it did say to drive the car rather than just let it idle up to operating temperature). The 997 manual makes no mention of the need to allow the car to warm up.

I have always assumed that the focus on water temp rather than oil temp was due to the fact that the water temp probably more accurately reflected the temperature of the engine parts, and that the oil simply absorbed heat at a slower rate than the water. Since the relative expansion of the engine parts is presumably what matters when you are warming up an engine, water was a sufficient proxy. If this is true, then what has changed with the modern engines? I mean, I know that oil technology has changed tremendously, but, under the theory I posited, that would be largely irrelevant (unless it is just so much better at lubricating that differing expansion rates could cause less damage in cold motors). I have noticed that the 997 comes up to operating temperature even faster than the 996 did. What am I missing?

[racer]

Modern cars are designed to heat up quickly to reduce emmissions. I found out the same with my Boxster - heck, the thing has 4 cats! I would start it and drive "gently" until the car is up to operating temp - in this case water temp.

Glad to see some people still read their owner's manuals.. and not just the "cheat sheet" pages

[Gator_86_951]

I have experienced this with the car I just bought. The thing heats up to operating temp like super fast. It is also all aluminum etc... I don't think you are missing anything TD. Also, you probably won't keep that car long enough to see any "damage" you would cause by pushing it too soon.

[VaSteve]

New cars are dummied down. The temp gauge is on a buffer so that the owner doesn't notice the fluctuations due to sitting in traffic or cool days. Only in a real issue will it move off normal.