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Positive or Neg ground, should I switch?

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I have converted a number of cars, primarily to run a more modern radio, the articles that I have read have said that coils don't care if it is positive or negative ground, will work either way, but will work better if you reverse the two small wires that go on either side of the big lead in the middle.

But I am no electonics expert and maybe there are positive and negative ground coils.
 
Michael Oritt said:
The supposed advantage to positive ground is something about electron flow, way over my head.

Unless you are a slave to originality I prefer negative ground if for no other reason than finding replacement parts for electronic ignitions is just a bit easier as it is more common. Yes, I know Pertronix and probably all the others have Pos ground units but they are not as common and in a pinch might be harder to find.

Plus the whole concept of "Positive Ground" continues to go against the grain for me.... It's simply easier for me to think in terms of "positive equals hot and negative equals ground".
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I agree with you Mike...<span style="font-style: italic">It's simply easier for me to think in terms of "positive equals hot and negative equals ground". </span>To ADD to this you want your car to "positively" grounded so that may mean "to have a good solid ground". A "negative" ground could mean a loose ground. And, people who are "positive" are much more fun to be around than those who are "negative". OMG...I actually went to(and graduated), from Aircraft Electrical school when I was in the Navy.
Patrick
 
Patrick--

Well I certainly like your thinking so the issue is settled!
 
Well my `55 F-100 is still 6 volt and positive ground. My `53 Farmall Cub is still positive ground. But someone converted my `41 Ford 9N to 12 volt negative ground and alternator before I acquired it. If you upgraade to an alternator for more modern day conveniences, then would change over. Otherwise, I dont see any reason. I think a fuel pump is about the only thing that could leave you stranded. I may be wrong, but generic universal electric fuel pumps, that you would actually find on the shelf, are not polarity sensitive.
 
I have always wondered about what would be the result of a positive ground car backing into a negative ground one and their bumpers somehow locking. What would happen?
 
But I have however, jumped a car with a dead battery from one with a good battery when the good samaritan only had a single cable. Glad we still had chromed steel bumpers in those days.

My then girlfriend's AMC Rebel, was prone to playing possum at the damnedest times, and another young buck with his dad's late 60's era Bonneville came to the rescue. The funniest part was him telling me how many people he had turned down jumping their cars because of only having 1/2 a set of jumper cables.

Michael, besides the bumpers touching, you'd have to throw a cable across the opposing battery terminals to create some real sparks. Both of the cars in my example were negative ground, so the single cable to both the battery's positive terminals allowed him to start her car. There was a little arcing at the chrome though...
 
"Michael, besides the bumpers touching, you'd have to throw a cable across the opposing battery terminals to create some real sparks."
---------------------------
Randy--

Yeah, sometime between sending the first message and reading your reply I figured that out. But I guess we should still have an OSHA warning on all + ground cars warning any good samaritans with - ground of the potential danger in helping us poor LBC'ers?
 
Michael Oritt said:
I have always wondered about what would be the result of a positive ground car backing into a negative ground one and their bumpers somehow locking. What would happen?
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I'm not sure what would happen, but like velcro with "hook & loop" also much better known as "male & female", I guess that would mean if they were male and female bumpers such as front and rear bumpers(if we could so designate them as such??
I'm really feeling <span style="font-style: italic">grounded</span> on this subject!
Patrick
 
"I'm really feeling grounded on this subject!"
---------------------------------------
I'm feeling energized!
 
Michael Oritt said:
I have always wondered about what would be the result of a positive ground car backing into a negative ground one and their bumpers somehow locking. What would happen?
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I believe, assuming good electrical contact, the cars would be electrically connected in series, similar to connecting 2-6V batteries from positive terminal to negative terminal to get a 12V circuit (like in the earlier cars). Nothing would happen--i.e. no sparks would fly--but if you put a voltmeter between a hot lead on each car you'd have 24V potential. Each car, however, would still only have 12V between chassis ground and a hot lead (with opposite polarity).

As an aside, "ground" is not the best term to use--nothing is electrically connected to the ground--"common" is more correct, since connections to it return the current to the source (battery).
 
Hello@all,

first of all, I wish you all a Happy new year.

I heard in the past, that cars with positiv ground had an affinity to corrosion. The reason should be, an electrolytical process meanwhile the positive electrode , the Anode (this does mean our car body...) is self-corrosive...

Also a reason should be sometimes, blocked radiators due to deposition of metal sludge.

The converse phenomehnon will be used for "cathodic corrosion protection" for example for boats.They use a sacrificial anode.

I`m not an expert,but it can make really a small bad influence. For not become depressive... :smile: for corrosion it needs additional an elektrolyt fluid and oxygen.

Bye michel- starts this year with an very bad english , sorry
 
Michael is right. One of my father's friends, a notabell engineer with BMC, told us once that the move to positive earth, sometime in the thirties I believe, was to reduce battery terminal corrosion. The move back again was not only to align with the rest of the world, but to reduce body corrosion. That must have been about the only thing the British mass-market car producers ever did to reduce body corosion, to judge by the way they rotted so quickly!
 
tahoe healey said:
If you should decide to convert to neg ground (I did) you should post the change on the battery and somewhere under the hood to let others know of this change. Assume nothing 'cause others will assume pos ground.

:savewave:
Now that is a good suggestion and if you go to your Land Rover Dealer he has some very nice signs "Positive" and "Negative: ground printed in Red and Black. you can put a proper sign in a highly visible place close to the battery and another on or near the control box.---Keoke- :laugh:
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<span style="font-size: 17pt">He's back! I just replied to your email BTW, in big letters. :laugh: </span>


Back on topic, Ahead for Healey has warning labels for neg. earth. Sadly, they don't have a photo of it. LABEL
 
RE, negative annd positive ground cars hitting bumpers, as stated nothing will happen, but.....when I was in college I had a '66 Sprite (positive ground) and my brother a '68 Sprite (negative). The '66 did not like cold weather, used the '68 to jump it on more than one occasion, one time the cars were close together and the bumpers rubbed is I got in and out of the cars. got an impressive show of sparks that cold morning!
 
glemon said:
RE, negative annd positive ground cars hitting bumpers, as state nothing will happen, but.....when I was in college I had a '66 Sprite (positive ground) and my brother a '68 Sprite (negative). The '66 did not like cold weather, used the '68 to jump it on more than one occasion, one time the cars were close together and <span style="font-weight: bold">the bumpers rubbed is I got in and out of the cars. got an impressive show of sparks that cold morning!</span>
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... because the battery cables were connected to each car.
 
There could have been carpet under the tires...
 
fordtrucks4ever said:
There could have been carpet under the tires...
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By rights, the rubber tires shouldn't have been conductive, but who knows how old (or hard) they were :wink:
 
Thanks all.

I think I will put the conversion on my list for next winter. Too many other projects running now.

With my luck the fuel pump will go before then forcing me to change asap.

Thanks all Scott.
 
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