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Old 07-31-2013, 06:03 AM
Anfänger Anfänger is offline
Location: New York
Join Date: Sep 2011
Posts: 69
Mein Auto: 2013 X3 35i
Originally Posted by Vortec4800 View Post
The variable steering means the steering ratio is different in the center compared to the edges of the rack.
It's called Variable Sport Steering for good reason. Without VSS the gearing geometry is constant; with VSS it is variable. With VSS the number of turns lock to lock is reduced, enhancing responsiveness as a tradeoff with sensitivity. To avoid making it too twitchy for driving in a straight line, the VSS effect (i.e., the gear ratio) is progressively increased at progressively greater steering angles. It reaches its maximum ratio at 90 deg, but it is still noticeable at narrower angles. So it's great for a hairpin bend, but it is also great for suddenly steering away from a pothole, or driving along a winding road. And you don't get this unless you have DHP.

Originally Posted by Vortec4800 View Post
Regardless of whether you have the variable steering, the electronic rack can change the steering weight on the fly, which is why you get the steering feel change with or without the DHP.
So in sport mode the torque sensor feedback is amplified? I couldn't see this written anywhere for the X3, though the table Liverman referred does support the idea. On the F30 blog it has generally been concluded that Sport mode only amplifies VSS sensitivity, based on comments like this one from BMW's blurb about "Sport Mode":

"If variable sport steering is chosen, the assistance from power steering is reduced, which ensures a more direct feeling of steering control".
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