This month we find ourselves testing ground wire systems and voltage regulators in The Lab. With much controversy surrounding the claimed benefits of these systems, we decided to get both sides of the story in addition to our own dyno testing model. Unfortunately, time constraints prevented us from getting accurate measurements of current flow and any good readings from our in-house oscilliscope to test the "cleanliness" of the signal. Still, we think you'll find the results of our testing quite eye-opening, regardless of which side of the electrical fence you're on.

NOTES : Because of the two separate test vehicles, some kits were not able to be tested on both cars (the del Sol battery is in the engine compartment while the Miata battery sits in the trunk, far from the front engine bay.) Also, other manufacturers were asked to participate but declined, saying that their particular kit(s) would only work on extremely modified vehicles. It's interesting to note that these manufacturers produce kits that are, essentially, electrically similar to the other kits tested.

The Players:
ApexI Super Ground System; Sun Auto Hyper Voltage System; Sun Auto Hyperground System; TC Sportline/HLH Ground Wire Kit; Lineage Motorsports Ground System; HKS Circle Earth Ground System

The Thinkers:
Klaus Allmendinger / Innovate Motorsports

Recently a spate of new products have come to market that improve "grounding" in cars. Sometimes the claims of what these products do are fairly broad, but the usual claims of horsepower improvements and lowering fuel consumption are pretty standard for all automotive aftermarket products, including seat-covers, floormats and cup-holders.

Let's look at the issue these products try to address. Every electrical system in the car (excepting the alternator) uses electrical power. Electrical power is defined as voltage (the "pressure" in the line) times current (the flow volume of electrons in electrons/second). Electricity ostensibly flows from the positive side of the battery, through the device, and back to the negative side of the battery. The negative side of the battery is also connected to the chassis or frame of the car; this is called the "ground". In many cars, the negative side of the electrical device is connected just to the nearest hunk of metal in contact with the frame. This can cause problems under some circumstances. Here's why:

Ever been under a nice hot shower while somebody else in the house flushes a toilet? The nice warm water stream suddenly changes to scalding hot? The reason for that is easily explained and the same principle applies to grounding issues. When water flows through a pipe there is a certain pressure loss along the pipe. The pipe creates a resistance to the water flow. The smaller the pipe, the larger the resistance. This resistance lowers the pressure at the end of the pipe (shower head) from the original pressure where the water main enters the house. If another outlet on the same water pipe also uses water, the flow in the pipe to both increases and more pressure loss results. So now your nice balance of and cold water is upset because less pressure is available on the cold water side of the shower valve.

In electrical systems it works the same way. Anything that conducts electricity has a certain resistance to the electrical flow. The electrical flow is measured in Amperes (A) or Amps. 1/1000th of an Ampere is a milliAmp (mA). In electrical formulas the symbol for current is I.

The electrical pressure (equivalent to water pressure in a plumbing system) is measured in Volts (V). Resistance is measured in Ohms (formula symbol R) The bigger the resistance of a supply wire, the more voltage builds up along that wire (V = R*I). But because there is only a fixed supply voltage available from the battery, the resulting voltage available for the electrical device is less. Bigger wires have lower resistance and therefore lower losses.

If multiple devices share the same electrical return path (for example the frame), the currents of all the devices add up on the way to the battery and there is less voltage available for each, depending on the total current between the ground point and the battery.

Returning to our plumbing example above: If we would run a separate pipe from the water main to each water faucet in the house, there would be no scalding in the shower because the pressure losses from any faucet would only affect that faucet. Of course the other solution would be to run 3" pipes all through the house to minimize pressure losses. This of course would be much more expensive than running only pipes as necessary. It also only minimizes the shared loss effect, but does not eliminate it, like separate pipes would. The grounding systems on the market are the equivalent to that 3" pipe.

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