that rally performance car is setup for the track.
if you want a dirt rally performance, check with the people in the rally/motorsports forums.
i'll tell you know, it's might be expensive for rims and tires. then when you want extra travel in an independent suspension, that will be more.
you just dont crank down on the coil overs to gain that clearance of the tire to the fenders.
you might need longer arms and axleshafts.
btw, you never said WHY you need these things....