1. Check your rear driveshaft as they are to long for most wheel offsets.
I am using KM wheel shafts and dogbones (kyosho also fits).
2. Check your gas tank so its closes, seams like the o-ring expands from the oil in the fuel. The spring is also very soft. The xray tank lid and spring fits.
3. We had some differential gears that has lost teets, i am using xray diffs front+rear.
Also i am getting air in my shocks pretty fast, going to try other o-rings and kyosho piston shafts.
Stock clutch is good if you replace the thrust bearing (stock is crap) and insert a harder spring. i am using the new 1/8 xray sping (Us1) tigtened 0,05mm and a 0,5mm gap.
I am also using Ride springs black rear and mostly purple or red front.
Harder shock oils 550-650. Raise the shocks up together with the soft Ride springs. also try to use the inner rear camberlink hole (longer link) for a more progressive rear end. Use shims on the rear wheel hub to get more steering.
Sadly i had little time to test but the car seems fast and easy to drive