Armoured Cable Between Ignition lock and Coil

[A Sherratt]

Hi.
After thirteen months of welding underneath my P1800 I am now roadworthy and MOT'd.
Having read the discussions about 123 ignition etc I was/am considering changing my coil to a new unit, however, as you are aware there is an armoured cable between the ignition lock and the coil.
My queries for you are:-
a. What does this armoured cable do?
b. What effect does its removal have on the lock?
c. What do I need to do to upgrade to a new 'sports' coil i.e. do I need to put some extra wiring in etc etc.

Your help would be gratefully appreciated as I don't wish to make a hash of a perfectly good running vehicle or be off the road for another thirteen months!!!

Many thanks

[austingipsy]

You don't need to cut the armoured wire at all, take a feed from the fuse box to power up a new high power coil and leave the old one in place. Just swap over the wire from coil to condensor onto your new coil.

[austingipsy]

Oh and change the lead over of course ;)

[mike gilbert]

Another factor is how original or neat you want your engine bay to look. I didn't want extra coils and/or blanked off holes in my bulkhead when I fitted electronic ignition and a high voltage coil. Nor did I want the original ignition lock because they tend to break the keys off and leave you imobile. So I cut the armoured cable off and threw that and the ignition barrell away.
Then I cut the old coil out of its triangular bracket with a disc cutter, put the new coil into the socket (it was fractionally smaller circumference) and used some JB Weld to secure it. Painted coil and bracket black as original and fitted it back to the bulkhead. Fitted a period 60's circular chrome ignition barrell and wired it up which was no problem. The only give away is there is a postive and negative spade connector on the top of the coil, instead of just a negative. You might be able to see it if this picture uploads.
After all that i'd say the electronic ignition was a definate improvement, I'm not sure about the coil though

[Pedro Fandango]

Another factor is how original or neat you want your engine bay to look. I didn't want extra coils and/or blanked off holes in my bulkhead when I fitted electronic ignition and a high voltage coil. Nor did I want the original ignition lock because they tend to break the keys off and leave you imobile. So I cut the armoured cable off and threw that and the ignition barrell away.
Then I cut the old coil out of its triangular bracket with a disc cutter, put the new coil into the socket (it was fractionally smaller circumference) and used some JB Weld to secure it. Painted coil and bracket black as original and fitted it back to the bulkhead. Fitted a period 60's circular chrome ignition barrell and wired it up which was no problem. The only give away is there is a postive and negative spade connector on the top of the coil, instead of just a negative. You might be able to see it if this picture uploads.
After all that i'd say the electronic ignition was a definate improvement, I'm not sure about the coil though
did notice there was only one terminal on the original coil, i thought the other terminal might of been the dash end of the coil (the other side of the bulkhead)

[mike gilbert]

the 'other' terminal is the armoured cable

[Derek UK]

Clarification - A single wire goes from the ignition switch to the base of the coil to make the positive connection. This is enclosed in the armoured cable.

[Pedro Fandango]

the 'other' terminal is the armoured cable

Clarification - A single wire goes from the ignition switch to the base of the coil to make the positive connection. This is enclosed in the armoured cable.
ah i get it now, sorry folks

[Gordon Hunter]

I didn't want extra coils and/or blanked off holes in my bulkhead when I fitted electronic ignition and a high voltage coil.

For what it's worth (not a lot probably) and from what I understand (please correct me if I'm wrong), the longer the HT lead from the coil to the dizzy, the more likely the deterioration of the power from the coil to the dizzy along the HT lead (even more likely with an old deteriorating set of leads?).
The P1800 has a perticularly long main HT lead.
I don't know if any deterioration would be enough however to negate the use of an uprated coil, though I believe this might be why most rally / race guys will move the coil to be mounted as close as possible to the dizzy to allow the strongest possible spark.
Magnecor do a very fat set of silicone HT leads for the Amazon. I have a set on my P1800 with a high power coil mounted very close to the dizzzy on the top of the LHS inner wheel arch.
However I do now have a nice triangular blanking plate on my bulkhead!

Gordon

[mike gilbert]

Gordon,
it can't make that much difference or there would be a similar (if smaller) loss of voltage for the longest spark plug lead compared to the very short one to spark plug four, leading to uneven power between the cylinders. However the longer the lead the greater the opportunity there is for faults, degradation and failure of the insulation of the lead to occur. So for reliability I think a shorter lead is preferable. But I'm as clueless as you on the finer points of electrics.
Mike

[Gordon Hunter]

Sounds about right Mike.
I suppose a shorter main HT might make a very negligable if noticeable at all difference to the overall supply to the dizzy, but what would it really matter anyway for any advantage gained?

BTW apologies I didn't make Kimbolton. I meant to contact you.

Cheers,

Gordon

[austingipsy]

I didn't want to cut anything if I didn't have to. The ignition switch is a villanous item though so I just wired in a starter switch under the dash. You only have to turn the key to the first position to power the fuse box and thus the coil and there's no danger of corkscrew keys. Probably baffle most car thieves I imagine but also most AA guys too.

[mike gilbert]

"BTW apologies I didn't make Kimbolton. I meant to contact you"

You were missed Gordon - you and a bloody great Umbrella both.

[A Sherratt]

Many thanks guys.

Ausingipsy - am very interested to hear about your starter button option if you could email me a wiring diagram and advise of what type of button/relay you have used I would be grateful.

In relation to originality, although its not my strong point, I was going to put the coil in the original bracket as you have Mike.

My key was beginning to resemble a corkscrew and I have managed to purchase two new keys (£23 delivered) from Gem Security tel 0117 978 8676.
I was very impressed with the speed of delivery and they fitted first time.

Adrian

[Pigeon]

Length of HT leads is pretty irrelevant for the most part...

The longer the lead the higher its self-inductance; a higher self-inductance leads to a longer rise time for the spark. But the self-inductance of the lead will be negligible compared to the inductance of the coil. So this effect is of no importance.

There is also the possibility of loss of spark energy by coupling to other wiring or metalwork, but this can be easily avoided by routing the lead as far away from other metallic objects as possible. Layouts of ignition wiring on production engines suggest that it is rarely a significant problem anyway.

Do not use silicone leads, they suck. They are prone to degradation leading to mysterious running problems which follow no sensible pattern but disappear when the leads are replaced. Much better to use the proper copper-cored stuff.

[austingipsy]

Adrian, here's a link to one on ebay . It's plastic but looks like bakalite so it's quite neat. I took a feed off the cigarette lighter because it was easier to get at. Run that into one terminal on the switch then run another wire from the other terminal down to the starter solenoid.
That's it, stick the switch wherever you fancy, good idea to hide it, no chance of your car getting nicked then.
Turn your ignition key to the first position, that powers everything then hit the starter switch and bingo !

http://cgi.ebay.co.uk/PUSH-BUTTON-STARTER-SWITCH-HEAVY-DUTY_W0QQitemZ190133394936QQihZ009QQcategoryZ15329 QQrdZ1QQcmdZViewItem