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Why positive ground?

It wasn't just LBCs. If you go back far enough you'll find other makes (even American) with positive ground. Like so many things, there was no standard. I suspect it wasn't until people started adding a lot of accessories to their cars that they needed to decide on one ground or the other.
 
At my age I have difficulty sorting out my anodes from my cathodes, to say nothing of electrons and things.
However, it was done, starting in the late 40s - early 50s to reduce battery terminal corrosion. Up till then, in UK anyway, negative earth was common.
Of course, reducing terminal corrosion increased body corrosion, so cars rotted (even) faster.
 
Therefore, you don't have to refresh your low cost battery as much, but you have to replace your car twice as much.......I smell a conspiracy! /ubbthreads/images/graemlins/devilgrin.gif
 
I thought that my MG was postive ground because the English have to everything different. They do drive on the wrong side of the road.
 
Interesting topic.
There are positive ground system because like anything new there were no standard at the time.

Remember the Ford Model T. 3 pedals on the floor from left to right(1st 2nd gear, reverse and brake) and the accelerator is on the sterring wheel.

That was before standards were established.

By the way if you remember Physics although the standard mentions that electric current flows from the positive to the negative in actual reality it flows the other way around.

Thus positive ground system would actually make sense...
 
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It's interesting -to me at least- that all of the threads on converting positive to negative earth never mention the body/frame corrosion issue. How much does it contribute??

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Interesting thought. But I wouldn’t think it would matter one way or the other.

To all those little electrons the body of the car is just pathway to get where they need to go. So a rusty body wouldn’t make anymore of a difference to the direction of the electron flow, than a road filled with pot holes would be to you commuting to or from work. /ubbthreads/images/graemlins/wink.gif
 
Because the body would actually serve as the return circuit.
 
Eric, The body of all modern Neg ground cars serves as a returtn path???----Keoke /ubbthreads/images/graemlins/yesnod.gif
 
Yep 703MGB,Remembered those Model T Fords Probably coppied those Liquid Flywheeled Daimler cars from across the pond.---Keoke /ubbthreads/images/graemlins/patriot.gif /ubbthreads/images/graemlins/laugh.gif
 
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Why did the earlier LBCs have positive ground?
Lonnie

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I once read That the English thought there would be less corrosion of the chassis metals with a positive ground system. Ford used it in the 1930's also. I've never been able to substantiate this idea. Can't imagine why Brit cars needed corrosion protection in the first place. /ubbthreads/images/graemlins/grin.gif
D
 
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It's interesting -to me at least- that all of the threads on converting positive to negative earth never mention the body/frame corrosion issue. How much does it contribute??

[/ QUOTE ]----------- Body/Frame corrosion is less of an issue now because a common metal is predominantly used throughout the car.---Keoke

Interesting thought. But I wouldn’t think it would matter one way or the other.

To all those little electrons the body of the car is just pathway to get where they need to go. So a rusty body wouldn’t make anymore of a difference to the direction of the electron flow, than a road filled with pot holes would be to you commuting to or from work. /ubbthreads/images/graemlins/wink.gif

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Now Bret, I think if you saw a bunch of pot holes in the road commuting to or from work you would try to avoid them. Those little electrons are just as smart and they would try to avoid the pot holes,Rust Spots, too, preferring to travel easier in good metal.---Keoke /ubbthreads/images/graemlins/yesnod.gif
 
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Because the body would actually serve as the return circuit.

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The body serves as part of the circuit regardless of which polarity is grounded. One way, it's the supply circuit, the other, it's the return circuit. If one approach decreases corrosion and the other increases it, I'd like to know how and why.

I sure hope someone can provide a definitive answer to this question, because it has puzzled me for a long time. Somewhere, in the annals of the past, there must be a scientific paper that gives the rationale for each of the two options, and for the conversion. I've looked for it, but haven't yet found it.
 
/ubbthreads/images/graemlins/savewave.gif
Just a quote from the late Geoff Healey in a conversation I had with him years ago in Colorado; "IT was just the practice at the time"---FWIW---Keoke
 
Also,the spark jumps the opposite direction on the plugs. Take a look at the wear patterns on plugs pulled from each type setup. on a standard neg. ground car the center electrode wears. on a pos. ground car the electrode tab tends to wear more. It was reported to have increased plug life and provide a slight(and I mean very slight) performance advantage.
 
No No Banjo we put Lucas theory to bed long time ago. The polarity of the spark in either system is the same.--- Keoke /ubbthreads/images/graemlins/yesnod.gif
 
OOOP, My bad, I'll take your word and double check my sources (he promised that was right... Maybe I should take another look at the deed for that bridge he sold me)
 
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