I too really wait for that one.
Looking at this link could be useful :
http://www.xray-shop.at/shop/index.p...5psqcrpb7tu1q4
From my understanding the dirt car will be built around a regular mid gearbox (motor should be close to diff for more rear grip) that could be reversed for a proper rear motor. Most of the composite parts of the dirt edition could use medium composite for flex. Ball diff. Composite shock tower.
Carpet car will be built around a low rider gearbox using hard composite for less flex. Gear diff. Carbon shock tower
Beside that Aluminium parts will be available (steering, rear hubs, front hinge pin block, front center link holder, etc).
Graphite arms also for carpet car for ultra high traction.
That seems a very good idea to go that far playing with composite blend, pretty impressive.
Still wondering about composite and carbon chassis.
Please bear in mind I just try to understand where they are going from the parts list, I have no info from Xray or else, just very excited about that car. So pure speculation, not real info from Xray.