Warren:
I was ready to post something to this effect yesterday as well. I hope they were comparing apples and apples, though, long chassis to long chassis. I went to the 220 model intro (not technical training, that came later) it was mostly for sales guys. I believe you are right that the interior space technically was pretty close to the W140.
According to one resource here at home, The 220 is 2.1 inches shorter (exterior) and 1.1 inches lower roofline than the 140, but that the 220 has 2 inches more rear legroom. The 220 is said to weigh 765 lb less than the 140.
Another source, Motor Trend Online, reported the 220 to be "1.4 inches narrower and 1.6 inches lower" than the 140, and that the drag coefficiency dropped from 0.31 to 0.27, and that it was 660 lb lighter. Also to quote "Despite it's more compact footprint, the car's generously proportioned interior dimensions remain virtually unchanged.".
Gilly

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