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T

thegoodbeamer

Jedi Warrior
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I need to know what is the polarity of the 1963 Spitfire.
I'm assuming it is Positive ground but not sure.I base this on the fact that Sunbeam alpines were positive ground for 1963.

Am I correct or is it negative grouind,
Thanks for any answers
 
Take a look at the battery polarity (+ or -)and see which side goes to a ground on the body. Which ever side is grounded is the polarity. These cars are been around for too long to think that it won't be changed.
Scott in CA.
 
Thanks for the reply

I do know all that.It would be easy if there was a battery and cables attached.

I was looking for a definite answer
 
Chuck,
is there a wired coil in the car?
A neg ground car will have the negative wire going to the distributor.
Tom
 
Tom's got it. the "ground" side if the coil is the points. so on a positive ground car, the positive terminal of the coil is hooked to the points in the dizzy. If it's been converted, the negative terminal of the coil will lead to the dizzy.
Hopefully your coil is still hooked up.
 
TFB said:
A neg ground car will have the negative wire going to the distributor.
Click to expand...
Assuming of course that whoever did the conversion or installed the coil did it right. They will run just fine with the coil polarity "wrong", and I've seen several running cars that had it so.

Some modern cars even fire every other plug "backwards" (to halve the number of coils needed for a distributorless ignition).
 
Then there's the possibility of the coil being marked "CB" & "SW"... :laugh:

Whatever the "correct" polarity should be, I'm sure that Andy Mace will set us straight on this. Or, you could just make it whatever you want!
 
Art, Don beat me to it by the better part of a day. Yes, the early Spitfire 4s were originally positive ground from the factory. But no harm will come to any electrical component unless it is polarity sensitive, and that's pretty much limited to a radio or an alternator (+ ground alternators are quite rare). Worst case scenario on an "original" car is that one might need to repolarize the generator. Even at that, I've actually seen generators "repolarize" themselves!
 
Thanks everybody.
Now I know for sure.The coil is still there and wired.
I was pretty sure that it was positive ground.
Try again next week or as soon as I get some points and a condensor I do have coils on the shelf
 
Don't forget to get the + ground points :wink:
 
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