Does anyone have any knowledge or any forst hand experience with one of these and if so are the any good and do they do what it says on the tin ?

 

Do you mean earthing kits (that's what i know them as) if so i've got 1 but since it's been on the car (93wrx) since i got it can't really tell you if it's good or not but the early classics, such as mine, the electrics are allegedly poor but since you've got a late model i guess you wouldn't need one.

 

Fair play, on my95 the volt gauge flickered sometimes and at night when the lights were on, on idle the they also slightly flickered but like you say I dont think i need one I just woundered if there was any advantage in geting one any way ?

 

Since they are only about £30 might be worth a go.
I do notice on mine (compared to others of the same year) i don't get the flicker of lights on idle.

 

These kits come in two flavours.

You get plain earthing kits, where multiple ground points around the engine bay area are connected by high quality wiring to a common ground point. HKS Circle earth is one variant, there are many other cheaper options. Logic is that any small differences in electrics are stabilised allowing ECU and all sensors to operate at max efficiency.

On my car I have a Buddy Club racing condenser. This combines voltage stabilisation (via big capacitors) with a common grounding point capability. Again logic is that if ground and V+ are stable, everything works better.

Sales blurb mentions improved idle, fuel economy and power for these kits. Buddy club website shows a standard WRX gaining 9bhp from the fitting of stabilisation kit. Guess impact would depend on individual car and mods, but don't see how they can be a bad addition to any engine bay.

You can see the buddy club model fitted in the engine bay of the WR1 impreza (Osaka) in the current Max Power Jap tuning edition.