Originally Posted by mike3000fl
DS shifts much higher than D.
D basically granny shifts at a lower RPM for a smoother shift and better fuel economy.
DS holds it in gear until close to redline.
The fuel injection program and ignition timing probably gets more aggressive in DS also. (dont know this for sure but it would make sense).
"If you floor the car"
It will just shift at redline in both. DS usually when you're not flooring it just holds one or two lower gears than normal to give you better response.