ok....i have a page that i found i hope this helps a little
RS FOUR, PRODUCED FROM 1996 (SEPTEMBER)
-Fuel consumption l/100 = 12.9
RS FOUR, PRODUCED FROM 1997 (JANUARY)
-fuel consumption at 10-15 modes, l/100km = 12.9
25t RS FOUR, PRODUCED FROM 1997 (AUGUST)
-Fuel consumption at 10-15 modes, l/100km = 12.9
25RS FOUR, PRODUCED FROM 1997 (NOVEMBER)
-fuel consumption at 10-15 modes, l/100km = 12.1
25t RS FOUR V, PRODUCED FROM 1998 (AUGUST)
- Fuel consumption at 10-15 modes, l/100km= 11.3
25t RS FOUR S, produced from 1998 (august)
- Fuel consumption at 10-15 modes, l/100km = 10.6
25t RS FOUR V Produced from 2000 (june)
- Fuel consumption at 10-15 modes, l/100km =11.3
25t RS FOUR S, produced from 2000 (june)
- Fuel consumption at 10-15 modes, l/100km =10.6
25RRS FOUR, produced from 2001 (april)
- Fuel consumption at 10-15 modes, l/100km =11.1