How to get a good ground in your Mopar

67Dart273 said
You said it, now you prove it:

How is having a completely separate ground system (these are not wood boats) better than using the WELDED unibody platform?

Can you prove this by means of accurate voltage drop testing? Can you prove it's more reliable?

I certainly can see your point about a separate, bolt on object such as the rad support, so DON'T use the rad support for a ground!! If you always use good connections to the WELDED central structure of the unibody, that is plenty good enough, and so far as RF noise, is probably better.

I would bet you money, that even CRANKING a big HP BB/RB, that you cannot measure the ground drop across the unibody proper AS COMPARED TO your advocated separate ground cable to the trunk.

Should of seen that coming.

How is having a completely separate ground system (these are not wood boats) better than using the WELDED unibody platform?

It is not a completely separate ground system. What I advocate is bonding certain areas with adequate cable so you know you have a good ground.

Can you prove this by means of accurate voltage drop testing? Can you prove it's more reliable?

Yes and yes.

I certainly can see your point about a separate, bolt on object such as the rad support, so DON'T use the rad support for a ground!! If you always use good connections to the WELDED central structure of the unibody, that is plenty good enough, and so far as RF noise, is probably better.

Thank you, and I think we need to clarify that we are talking about typical Mopar unibody construction that has the rad support welded to the front frame rails and inner fenders. As an example, Mopar headlight wiring typically is grounded to the rad support, which was welded to the frame rails and inner fenders, which was welded to the firewall, which was bonded thru a strap to the back of the engine block, which was attached to battery - thru the battery cable. Add 40 years of rust and corrosion and any point of failure will affect headlight performance. Don't really care about RF noise at this point, but it is an added concern.

You place a lot of emphasis on welding. Welds can fail and in unibody structure, this can lead to poor electrical performance without detectable structural issues.

I would bet you money, that even CRANKING a big HP BB/RB, that you cannot measure the ground drop across the unibody proper AS COMPARED TO your advocated separate ground cable to the trunk.

Keep your money. I've made lots of it fixing this very problem for others. Actually, you are likely correct that you may have difficulty measuring a drop across the unibody proper, but the difficulty is in providing an adequate bond from the cables to the sheetmetal.