Explain to me the quattro diff set up.

 

Torsen center diff, open diffs front and rear, locking diff action provided by the brakes

The TT system uses a Haldex center diff instead of the Torsen

The difference between the two: Torsen fully mechanical and the Haldex is electronic

 

Three diffs, wow.

 

What % drivetrain loss can be deducted from crank HP numbers due to the quattro system? How much heavier is the quattro than the FWD A4s?

 

25% drivetrain loss and its an added 300+ lbs. 15% loss for fwd.