The differential used is a Torsen centre differential from an Audi Quattro. Drive
shafts have been installed in both outlets of the differential and provided with
lever arms at their ends. The levers are held by an infinitely adjustable balance.
If the differential housing is turned with the help of a rotary lever, the levers
of the axle shafts contact the lever arms of the balance. Depending on the setting
of the lever arms on the balance, the differential blocks until the balance has
been adjusted in such a way that the differential slips lever arms. The locking
figure of the differential can be determined immediately by reading off the lever
arms (law of levers!).