I ended up pulling the engine and clearancing the center diff top plate a little more so even with the chassis flex the boot doesn't touch at all now.....



On another note:

How many shims does everyone use with their GRP .21's? I'm currently breaking in the GRP Non Tuned .21 in my losi and I added one extra 0.1mm shim before I started it just to take a tad bit of compression away. I'm running 30% fuel right now. Are the non tuned engines shimmed from the factory for 30%? So once I finish break in should I remove that extra shim?