Suppose it does a lot, but i'm pretty sure it's all BS. But if HKS has the ***** to BS it must have at least a little bit of gain. So i'm wondering if it's just a bunch of wires can't i just make that at home. If anyone owns this system i just need to know what parts of the engine bay needs to be grouned. thanks

 

the reason that this makes a difference is b/c the ground wires used are like 99% pure copper, on top of that it uses multiple grounding points so the current will flow better; as far as i know you'd see teh most gains in more of a "race" engine b/c more power & such = more current.

 

Unless your current wires are in poor condition, there will be no improvement in performance. The factory system as designed is adequate for the job it's supposed to do. You can add or 'upgrade' the ground straps all you want, but once there is sufficient conductivity to ground, the rest is just overkill.