Guys, have You realized that all car classes have grown through the years? Recent superminis are not so small in term of the rally history. See...

Lancia Stratos 3,71 m
Audi Sport Quattro 4,16 m
Peugeot 205 3,70 m
Lancia Delta 3,90 m
Toyota Celica ST165 4,17 m
Lancia 037 3,92 m

Polo WRC 3,98 m
Fiesta WRC 3,96 m
DS3 WRC 3,95 m
i20 WRC 3,94 m
Mini WRC 4,11 m

It's almost same as You can see. Only the two-litre generation of WRC and gr.N brought much bigger cars such as Impreza, Lancer or Octavia.