What do they do and are they worth having ?

My zed is a UK TT AUTO if that makes any difference.

not too sure if they actually do anything noticable but worth having i think, all it does is links different parts of the engine and bay to creat a greater grounding affect. i shouldnt bother buying a kit. easily made with good 8 and 4 AWG I.C.E. cable.

All it does is a back up grounding point for the harness and engine components in case you get a bad earth to one connection. Agree with silverbullet though much cheaper to make your own harness and that way you can route it anyway you want and will probably look a lot nicer than the kit version

i have 1 from Pete Shrimp with the gold platted terminals, cant tell you if it makes a difference as cant remember what it was like before, but it certainly hasnt done any harm

I have heard good reports about them and like already said I have heard people say they havent noticed any difference. I am not sure about makeing your own tho? They are not very expensive items and TBH I aint sure they are cheaper than the suggeted ICE cables? What I was told is that with the way these engines are set up the earth can sometimes become a little bit weak and so you may loose performance. With the grounding kit this wont happen so even tho you might not feel any difference, you may well have done if it wasnt fitted?

thanks for the info people i think i will have one fitted just in case ;)