Sounds like the car was a hand full with the gear diff... Two things that might help are tires and messing around with the rear roll enter a little bit.... Along with the ball diff...( I don't have much time on carpet but I do on high grip clay so some things should be relatively close for set ups )
When is the next time your going to the track Lee..? Get some more time on this chassis and you should be able to keep up if not be better than the YZ-2..
I have driven my buddy's Yokomo and that car struggles for rear grip on high grip clay for stateside tracks
