text: Ah, the black art of diffs.
  Locked diff - not good, but not too bad providing you don't want to go round tight corners and don't mind more wear. Typically fastest in LFS for very few laps.
  Open diff - bad (the problem with the Vectra in the video a few posts back)
  Viscous diff - simple, but not brilliant.
  Clutch pack - the best LFS has, providing the settings are right. Getting said right settings is a pain. Commonly used as the centre diff in 4wd and drift cars.
  Helical diff - (ie Quaife, the one used in the Focus RS) ideal mechanical racing diff as it gives the most torque to the wheel with the most grip. Unfortunately not (yet?) available in LFS.