What about this article... is it false?
http://www.importtuner.com/tech/0405it_300zx/
DYNO 4: A'PEXi Ground System
Air temp @ 66.4 Degrees Fahrenheit
Temperature difference from previous run -7 Degrees Fahrenheit
Peak HP. 274.0
Peak TQ. 298.2
2000 to 3500 HP Range: 1 - 3
2000 to 3500 TQ Range: 2 - 4
3500 to 5500 HP Range: 1 - 3
3500 to 5500 TQ Range: 2 - 4
5500 to redline HP Range: 1 - 3
5500 to redline TQ Range: 2 - 4
Pros: Unlike most ground wire kits, this one uses a voltage stabilizer that requires you to connect battery power to the box.
Cons: This system costs much more than the traditional ground wire kits.
Parts Include: Ground distribution block, five ground wires.
Tools required for install: 10-mm wrench, 12-, 14mm socket and ratchet.
Dyno notes: Just like most ground wire kits, power comes from where you ground the wires. We found that grounding near the alternator and spark plugs works great but placing them near crank triggers tends to make power erratic.
Install time: 30 minutes