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Triumph TR6 - ignition wires gauge

I went thru the archives and decided I wanted magnecor's 8mm wires. LBC just lists 8.5 and 7mm.
I have pertronix and a stock coil, is it enough for the thicker wires. I assume there is a limit to how thick you can go (I've haven't yet seen 9mm wires). I want to put a better coil in when I'm sure which one to get. Would the 8.5's be too big for the stock coil? Is it a resistance issue?

73 tr6
c.a.e. emenhiser

Hi Chris - I have the Magnecor 8mms and am very happy with them. There is a lot more science to ignition leads than just the thickness. Just get 'em and forget 'em! (I got mine from LBC also).

Roger H

Sorry - should read "I have the Magnecor 8.5mms...."
Roger H

Go for the 8.5s, add a HO coil that suites your TR for ballast or non-ballast ign. system and gap the platinum plugs to 30to40Thou. Pertronix will handle this. The 8.5 wires will work with the stock coil but keep the gap back at 25 till you get the hot coil.

Rick C
Rick Crawford

The thickness of the wires is due to the amount of insulation round the conductor, a thin trace down the centre of the wire.
There is no difference in resistance implied by greater thickness, the extra insulation increases dielectric strength, ie makes it less likely a spark will find its way through the casing to a nearby piece of metal. So you want a thicker wire if you have a high output coil. Proper routing of the wires, dryness and cleanliness will also help prevent shorting out.
Some wires are solid core, ie they have real multistrand metal wires inside, others use a trace made of fibre treated with carbon to make it conductive. The solid wire type will cause interference with your radio or tape player but is probably best for delivering electrical charges to your plugs, the other type can suffer from aging as the carbon gets burnt and becomes less conductive the resistance of the wire increases.
You may find the size of the holes in your distributor cap will limit the diameter of wire you can use, on my 4a I have use wd40 to make the end of the wire slippery to get 8mm wire to work.

This thread was discussed between 25/04/2005 and 26/04/2005

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