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Electrical upgrades

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Baz

Baz

Yoda
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I think I'm ready to move into the alien world of Lucas.
I'd like to upgrade alternator, maybe ignition, but have a couple of complete newbie concerns.
The stock alternator puts out 55, GM conversion can put out 80 to 110. My question is, and I fear the answer, is the stock wiring harness able to handle that or would I need a new harness?
If I need a new harness, this is a no-go.
Switching an alternator shouldn't be a problem for me, would coils or distributors also need to be changed, hence my 'maybe' on the ignition? Battery also?
TIA.
 
What's your driver for the alternator switch? Reliability? More juice?
 
More juice.
With the lights on, my turn signals just illuminate and not flash unless I go over 2500rpm, when sitting at a stop light, it gets warm!
With the stereo on and always hot, that was the last straw really. I'd like powered speakers and, if available and not much hassle, electronic ignition...
 
You've got one of them fancy radio thingies in your car. I've only got engine noise and wind noise to keep me company. /ubbthreads/images/graemlins/grin.gif

Don't have much useful to add, I'm afraid, as I'm running a completely stock electrical system (positive ground, generator). I will say that you shouldn't be afraid of rewiring the car if necessary. I realize the later cars are a little more complicated, but the Tunebug was incredibly simple to do. Get the right harness, follow the diagram.
 
The alternater upgrade does not require new wireing. However, think about this, your wireing was designed for what it does and will do it IF all the connections and grounds are good.

Guess what you need to do, take apart each and every connection one at a time and clean em and reasemble.

YOU GONA LIKE THE RESULETS. And the best part this job is a freebe. Then think about alternator after all the resistance in the connections is taken care of.
 
[ QUOTE ]
your wireing was designed for what it does and will do it IF all the connections and grounds are good.

[/ QUOTE ]

I'd like 1.21 gigawatts. I did clean all the connectors earlier this summer while chasing down a ghost, and the problems really only started when I put a new stereo in.
I'd like small powered speakers and not have my lights dim when I slow down either, so I do want it to do more than it was designed for.
As long as the wiring can stay put, I'm happy, I'll slap a Delco unit in there, 80 is enough.
 
There ya go. I considerd it but decided not, no radio and only use em for talk shows in any case.
 
Hello Barry,

if your stock alternator is 55 amps then that is quite a lot of power (660 watts. Just how much load is your stereo even with powered speakers? All I suggest is check the existing installation first, and start with the fan belt tension.

If you do fit a larger alternator, you should uprate the cable from the alternator to the battery, probably connects to the starter solenoid, this is the large brown cable. The loom doesn't need any alteration.

Alec
 
I am using a Delco on my car. Internal regular, puts out 14.5 volts constant at all engine speeds. NO more dim lights, slow turn signels,ect,etc. I did use relays for the high and low headlights so you do not run full amps through the switches. Big stereo and speakers ( I like my music guys).
https://i97.photobucket.com/albums/l221/cbeedle2/DCP_0021_1.jpg
https://i97.photobucket.com/albums/l221/cbeedle2/MyPictures.jpg
https://i97.photobucket.com/albums/l221/cbeedle2/DCP_0020-1.jpg
See if these links work
 
Music is not my goal, only have a $99 Sony in there. The previous dealer installed 8-track finally quit and played Hugo Montenegro over and over and the only stations I could pick were sports/politics/jesus on AM.
My goal is an attempt to offset the Lucas improbability drive by trying to stabilize electrics such as Taz mentioned above, just reliability and a window for more juice. The last thing I need is my electrical system going all HAL-9000 on me on the way to work.
I looked at that cable Alec and will replace it, mine is black and looked pretty manky.
I've never installed (or heard of) a relay before but I understand they are a sturdy, safe feature.
I think I'll outsource this job to the shop.
Thanks gentlemen for the hints.

Should I change coil and dizzy while I'm at it?
 
If it ain't broke don't fix it. hehe.
 
It's Lucas Jack, it was broken before it left the factory.
I understand though, there's nothing wrong with the dizzy or coil (to my knowledge) so I'll leave that as is.

Taz, what bracket do you have on the rear mount of the Delco?
 
Hello Barry,

unless the cable has been replaced, or is severly discoloured then the only black cables you should have are earth cables. In most British cars of this era the main alternator power cable runs from the alternator to the starter solenoid terminal which also shares a connection with the battery positve terminal.

It is, in my opinion, silly to say that the problem is because it is 'Lucas', particularly as very often the problem is simple neglect or lack of knowledge. The other factor to bear in mind is that the components Lucas supplied were engineered to a price dictated by the customer, i.e. the car manufacturer. Lucas today is an Aerospace component manufacturer, not the sort of business that tolerates unreliable equipment.

Relays are a good way of reducing the current carried by the control switches but at the expense of added complication, and could be hazardous or more troublesome if an incorrect design or installation is carried out. The original switches are rated for the intended load, so to believe that relays are an automatic plus factor is not necessarily correct.

Alec
 
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