View Full Version : Earth Grounding Kit

26-01-07, 01:12 AM
Guys i am currently in the process of designing an earth grounding kit specific to the 300zx, i understand this does not suit anyone on here other than myself, but am looking at expanding into other cars, cost of kits on 300s is 50 for 4 points and 90 for 8 points, does not include voltage stabilizer like a lot of the expensive kits but has gold conectors and uses a combo of 4 and 8 guage wires, looking at expanding into other cars as the market for 300s is not huge, is anyone interested in doing a deal where by i spend a few hours with you and your car under the engine bay designing a kit specific to your type of ride (obviously for a discount) and would anyone be interested in purchasing a kit. These kits are top quality and can come in black or red. A lot of performace places charge $200+ for such kits and do not use as high quality components only differentce is they come witha voltage stabiliser which imho is not nessacary, a bit of info has been provided below but people have noticed the following with similiar or lower quality kits - Improved idle, increased power, brighter headlights, louder soundsystem. This mod is a must for anyone with an aftermarket soundsystem as it reduces that forever painful lights dimming when the sub kicks in, and i know with my car i need all the power from the headlights i can get as the stock lights are not the brightest, lol.



Taken from tech section on Aus300, but can be applied to any car

Recently, more attention has been paid to the benefit of providing multiple ground points to an engine. There have been plenty of articles in enthusiasts' magazines that show small but significant increases in horsepower by simply adding additional ground or "earthing" wires. "Import Tuner" magazine showed a three horsepower gain on a 300ZX NA using an A'PEXi ground kit. Their kit cost over $200 and used a voltage stabilizer. Proponents also point to easier starting, smoother idle, brighter headlights, and improvements in just about anything electrical in the car. Whether or not you're a "believer," this mod is safe and inexpensive, which is more than you can say about a lot of other mods we do to our Z's.

This explanation is mostly conjecture on my part. Conventional thinking used to be that grounding was an "all or nothing" phenomenon. Either your car battery was grounded, or it wasn't. The amount of electrical current running through the negative battery terminal is equal to that running through the positive end. The battery represents part of a giant, complete circuit for everything electrical in the car, no matter how far away that component is from the battery, or more precisely, the battery ground.

The stock, negative battery cable on my '92 TT had TWO grounding points. The first was right next to the battery where the cable was stripped bare and attached to the firewall. I modified this ground point when I put in my Optima battery with the black DC power line shown, but this is a stock ground location.

The cable then continues down and attaches to the transmission bell housing. Interestingly, a Nissan parts technician whom I respect told me that replacing the negative cable without reusing both stock grounds was a known issue for the Z not running right. So even the stock set up is apparently designed for two, and not just one battery ground. Logically, if two grounds were better than one, then more than two grounds might be better still.

The distance and thickness of the metal between the battery grounds and the various electrical components of the car vary considerably. This creates differences in resistance, which in turn creates small, undesirable variations in voltage at different points around the engine and car where electrical components are in use. This includes everything from the fuel injectors to the dash lights. The extra grounding wires improve the current flow back to the battery by lowering the resistance with multiple paths, allowing for more reliable and consistent voltage.

The way in which extra grounding points could improve horsepower is probably through cleaner data transfer to the ECU (Electronic Control Unit, or the car's central computer). The ECU controls multiple engine functions. IMHO, the single most important of these functions that could benefit from improved grounding is the timing and duration of voltage pulses to the fuel injectors. There are probably additional benefits for all the engine functions controlled by the ECU that result in more accurate performance, smoother idle and better acceleration.

That's my story for now and I'm sticking to it. Feel free to contact me through this web site if you have any constructive criticisms.

Earthing or grounding kits are hot selling aftermarket items that didn't even exist a few years ago. Nismo, the racing division of Nissan, makes one for the new 350Z. Prices of these kits can run upwards of $100 to $200.

26-01-07, 10:43 AM
we did back to back ground kit testing of a few kits, on 3 different car back in the day.

we used a DIY jaycar kit
an expensive HKS circle earth kit,
and a cheapish off the shelf kit.

we put them on,
an NA FWD piston car
turbo AWD piston car
turbo RWD rotary car.

dyno tested and left the kits on for a few weeks to see if there were any benenfits.

dyno testing revealed nothing.
all drivers didnt notice any benefits with the kit fitted.

Justin Fox
26-01-07, 11:00 AM

Dyno tests have proven gains with the Buddy Club Racing Spec Condenser. It's a little more than a simple ground wire kit though as it's an electrical grounding system with a battery current and voltage stabilization control unit. IE: Not just a ground kit, it is a voltage stablizer.

Having said that. I think old cars, like AE86's for example, could benefit from a simple ground wire kit as their grounding might not be as good as it used to be due to old age, wear and tear.

26-01-07, 10:30 PM
that may be something to keep in the back of my mind justin, when the new engine is about to go in...

26-01-07, 11:25 PM
The gains i noted in the forst thread are actual gains from real people i have spoken too, have not spoken too anyone that has gotten power out of it and anything you do would not matter at the end of the day really as wtf is 2 extra kw going to do, i have read that 10 earths is the point where it starts to become pointless and as my car coomes stock with 2 i think it needs a few more, just thought some of you may be interested