Ils sont malades ces francais!
I knew people rallied Specially built 959s in the Paris-Dakar years ago and other purposely build 911 in other rallies. These cars rode much higher than regular 911's and were prepared specifically for that purpose.
The GT3's in this video seem to be the regular height (although it s a bit hard to tell).
In any case this video really supports the Motto "There s no substitute"