Grounding cable? I bought mine (5 pcs) from erictioh. To be honest if there's any improvement, I'm not noticing it probably because I hadn't really observe how the car was like before the addition of the grounding cables. Maybe I'll get around to removing the cables to see what difference it makes, although it may be never because it's quite a hassle to deal with the removal and installation of grounding cables especially if you don't have the right tools.