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ground wire system

31 May 2007
do you guys know how to install the ground wire system on engine bay?
any pics or DIY would be great if there is any. i just dont know where to start. tks in advance.
pretty straight forward.

the point of the grounding wire is better connection for the current to travel from the engine to the chassis and back to the battery.

pick a clean point to the chassis. Connect one of the wire to that ground and then start connecting wires to the engine, intake manifold, tranny.. whatever.

there is no set way to do this.

just remember. the current needs to travel from one side of the battery to the other. So less the resistance the better.

usually I just get a $3 negative battery cable and hook one side up to a fat tranny bolt and the other to the chasse. I usually pick a strut anchor bolt.

happy grounding.

Do you connect any wires to the negative side of the battery or just wires to the chassis and other components (i.e. transmission?)

Has anyone measured the radiator coolant voltage before and after installing additional grounding? I had a Ron Davis racing radiator develop a leak after a few months and they suggested I check the coolant for voltage to determine if electrolysis from inadequate grounding could be the cause of electrolysis and the leak.
tks guys!!!
I have experienced grounding problems with my NSX. It's a turbo with many after market electrical components....i.e. water pump, scavenger oil pump, electronics, stereo components, etc. The ground connection for my turbo's oil scavenger pump once failed. It was connected to the aluminum chassis. I reconnected it to two chassis points and that solved the problem. My AEM serial gauge also is affected by "noise" that my tuner says is from chassis grounding sensitivity of the AEM. He mentioned that Hondas tend to have a problem with grounding that affect the older AEM ECU's. He had to maximize the noise filtering of the AEM.

I just installed a new Ron Davis aluminum radiator. It came with a "yellow sheet" explaining the need for good grounding to prevent electrolysis. I just called Ron Davis and they told me that an all aluminum car like the NSX will have less effective grounding than a steel car. They recommend testing the radiator water for voltage and say that zero to .3 volts is normal and that .5 volts can destroy an engine in time.

Summary of instructions to test for voltage (poor grounding):

-Test voltage with one probe to the battery Neutral and the other probe to the coolant only.
-Turn on all electrical components and test for voltage in DC and AC.

-Read the DC and AC with the electrical starter engaged.
-Turn off one component at a time to see which component causes the voltage. Ground that component.
-Be particularly careful of starters. "They can cause as much damage to an engine as a direct connection to an are welder due to amperage present."
-"Always change coolant if current is detected. The electrical current will destroy the protecting chemicals in a properly inhibited coolant."
- Grounding transmissions & rear ends is highly recommended.

I asked what gauge of wire and how to ground:
-They said 18 gauge is adequate on most components...Use larger i.e. 8 gauge on the starter.
-For the NSX they recommend grounding the components to the chassis and to the battery because they told me that aluminum is not as effective at grounding as steel. They said we could use the existing wire that's in the engine bay that leads to the battery's neutral for the battery ground.

I haven't had time to test my coolant for voltage. It would be interesting to hear from others and see what voltage our cars are running.