In Reply to: say what!?!?!? posted by Brad Franklin on October 05, 1999 at 13:35:42:
Once an engine is up to speed, at normal operating temperature, WITH clean and continuous oil flow there is VERY little friction effect. This is a fact. I recall some guy like Smokey Yunick building a Chevy motor entirely on needle bearings, thinking this would have almost no frictional drag. Turned out the motor was no better than a conventional engine for the exact resons described above.
The wear and tear on an engine largely occur at the times of startup/warmup/and cooldown. Once an engine is running, it actually runs MORE efficiently in its designed RPM range. For a Honda VTEC this might be quite a high RPM I suppose. Efficiency here does not just mean volumetric efficiency (ie, timing and flow of intake/exhaust gasses) but can mean higher oil pressure as well. When an engine is up and running, the components float on a cushion of oil--this is why there is very little wear. At higher RPM's and with higher oil pressure, this cushion might be more stable. When the engine is started or stopped, the cushion disappears and the components come to rest physically together. So what I am saying is, I believe, correct. Running any engine at a set RPM for a month with proper maintenance is no big deal. Starting and stopping an engine every few seconds, before it can warm up or develop good oil pressure, would be a true test of an engine's longevity.
: You guys gotta be kidding, running an engine like that will definitely wear it down! New engines are supposed to have a break in period to allow for some inital wear/ring seating before you really run the thing. One big reason why diesels last so long is that they never rev that high...