Just wanted to hear if anybody got their ohm meter out and checked.... I scraped the paint off a spot but it seems to have a so-so connection, so I want to get a nicer ground point. Much obliged for any help, the alternator whine in my car is slight, but enough to be very annoying :)

While poking around the trunk this evening, using my trusty Fluke 87 III and a 10 foot jumper wire (#12 stranded wire w/ alligator clips on each end), I set out on a mission. To find a good ground.

I first hooked one end of the jumper wire to the bolt on the negative battery terminal & one end to the negative meter lead. Placing the positive meter lead on the same bolt, I "zeroed" my meter in the Relative & 4 1/2 Digit Mode. Heading back to the trunk and under the rear seat, I checked all bolts, brackets etc. that have been recommended above. Most read from .00 - .01 ohms. I re-zeroed and read them several times and came up with the same readings each time.

While taking these readings and focasing on low impedence, I realized that I have foolishly been overlooking one of the most crucial elements of any electrical circuit. If I have a #2 power wire (which I plan on using for about 1300W), what makes me think I can ground this system to the chassis anyway when the largest ground from the battery is a #4? (Without tracing the 3 ground wires through the loom, I am assuming the large one goes to the starter & the smaller 2 to various body or electrical components.) Anyone remember which way current flows? I see catastophic failure in the future! The ground wire ALWAYS has to be as large, or larger, than the power wire. Why do we forget the basic stuff?