conversion back to positive ground

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conversion back to positive ground

Postby Sprite White Hope » Mon Nov 21, 2011 2:52 am

My 62 Sprite is neg ground. I noticed the tach says positive ground. I would like to convert it back to pos ground since that is the original. Is this recommended? How come some cars have pos but most have neg? Is pos better? Is neg better? How do I do the conversion? Thanks, Carl.
Carl Taylor
Bozeman, MT.
Sprite White Hope
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Re: conversion back to positive ground

Postby Asolepius » Tue May 01, 2012 9:40 am

This must break the record for a slow conversation! Nobody else appears to have replied, so I'll break the silence. I changed my Mark 1 to neg earth and would not contemplate going back. You get less battery terminal corrosion, it and enables you to fit modern accessories (eg the battery). I suggest you buy a neg earth tacho and save the hassle of re-converting.
Les Rose, Salisbury, UK
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Re: conversion back to positive ground

Postby MikeWood » Fri Sep 21, 2012 6:35 am


A related question - is there any advantage to staying with positive earth, apart from being able to use the dynamo powered mechanical rev counter and such 'originality issues'?

My reason for asking is that I am thinking of retiring my Mk2 Sprite and the conventional wisdom is to switch to neg earth, as this enables a switch to alternators which have higher power outputs. But what if you can switch to a positive earth alternator, such as: I recognise higher cost and replacement issues compares to a standard Lucas neg earth model, and loss of rev counter drive, but any other issues for a positive earth alternator conversion compared to going neg earth?

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Re: conversion back to positive ground

Postby Ragnars-Frogeye » Fri Oct 05, 2012 7:09 am

Hallo folks,
my Frog still runs on positive earth. I don't have any problems with it. There are always enough amperes and volts to drive even in the night!
You're right saying today its easier and cheaper with neg earth. I can't see any reason for me to change to neg earth at all.
My Frog had had some changes before I bought it, the whole gauges are form Sprite 2. There is a pos earth tachometer included not the mechanical.
To change a tacho from pos to neg or the other way is no problem if you can solder. There are only a few wires to change!

I got a plan for an MG B in my computer, but it may be in German.

But if you visit my homepage there you can find a report form Marc Olson (you have to click on his name) who lives in the USA. He describes all you have to know about the tachs. To get to the English part you have to scroll a little. Also you can find there some firms who can help you if you click on Firmen.

Running on with positive vibrations on heart an Frog
Greetings from Germany

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