Difference starts at about 3200-3600rpms. A turbo will be at its full boost setting creating a ton more torque then a centrifugal supercharger that still isn't half way to making its full boost setting. That's right, superchargers don't reach full boost till your shifting. Where as a turbo reaches it before peak torque. Also a blower tends to eat 18-30% power loss or engine drag on the crank to turn it. That is just another reason why turbos always make more power at the same boost levels.
