-Plastic Diff eccentrics -10g in front of motor mount -Mistakenly ran 2.5 mm under front arms... intended to run 2.0 -Still has some traction rolling issues... try: -Hard Arms -Graphite Hubs -lower RC shims under arms 2.0/2.5 or 1.5/2.0 -7.5 mm steering rack -Horizontal Rear Body Mount -full stiff shock mount flex -thinner wing