Thnx for such a thorough answers. MB usually is conservative on their spec figures. I always feel that my '92 400SE makes more than 282hp. It says OFFICIALLY that 0-100km time for 400SE is 8.6sec. But no matter how many times I measure it, it will be some where around 7.4-7.7sec.(hey, maybe they put a 5.0L V8 in mine by accident....J/K).
As for the temp. sensetive issue. I did notice that when the day is hot, the car seems to "loose" couple HPs.
Well, anyways, thnx for your time to answer my Qs.