Does anyone know the torque spec for the big nut in the middle (sorry I don't know the right name) on the Cusco camber plates?

Also, what's a good alignment for a daily driver / autocrosser? I was thinking -2.5 camber front / -1.5 camber rear and 0 toe. Is that a little too much camber? Would -2 F / -1 R be better?

Thanks

 

The big bolt in the middle of my driver's side camber plate keeps loosening up and is shifting around. In comparison the passenger side is staying tight and doesn't seem to be moving. Does anyone know what might be wrong?