The GTI-R is a constant 4wd 50/50 car, it does NOT vairy the split between front and rear at all.
The GTI-R does not have the same 4wd system as the GTR, it may share a similar name but they are so unrelated!
the GTI-R uses a center diff which is not variable, and can not be adjusted to split torque, only a worn/broken diff will cause the gti-r to be more rwd
The GTR uses a transfer case with clutches belts whistles etc to split torque between front rear and is controlled electronically and can be varied with controllers
And thats all folks!!! Trust me i have owned both, and pulled apart both!!