Pretty sure standard ones are 20.7.
Golf V GTI: 23,6 x 3,5 / 21,7 x 3,0 both tube
Golf V R32: 22,0 solid / 21,7 x 3,0 tube (4-motion)
Golf VI GTI: 23,6 x 3,5 / 21,7 x 3,0 PR-0BF or 21,7 x 3,6 PR-0BM (DCC?) both tube
Golf VI R: 22,0 solid / 21,7 x 3,6 tube (4-motion)
Scirocco R: 23,6 x 3,5 / 21,7 x 3,6 both tube
Touran 170 HP: 23,0 solid / 21,7 x 3,0 tube
Passat R36: 23,6 solid / 21,7 x 3,6 tube (4-motion)