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MG MGB GT V8 Factory Originals Technical - lumenition - any good?

I've recently seen a lot of adverts for lumenition ignition - both a simple conversion to replace the mechanical breaker points in the distributor, and a more advanced performance option. Is anyone using these? Is it a worthwhile investment for 100 - 200?
Chris Holmes

Chris, when I had my 'B all those years ago I had one fitted and found the results mixed.

* Plug life
* Starting
* Idling
* Fuel consumption
* Performance.

* Consistency of performance between tune ups
* Exhaust emissions.

Fitting one does eliminate the time and cost of points replacement and the gradual deterioration of performance as the points are worn and deviate from the makers specifications (which also can vary too by the way.)

Obviously it is your decision to balance up the costs versus benefits in your particular case.

I often think the benefit depends on where your original distributor is to begin with. If it is badly worn and no where near the makers specs then any improvement will be substantial. If on the other hand it is well maintained then the benefits will be marginal or perhaps nil.
If the bushings are in need of replacement or the drive gears are well worn then they still will be after too and the performance will not be there.

The other point is this is only an electronic version of the "make and break" part of the distributor; the rest of it is sill mechanical.

Peter Thomas

It does what it claims - over some 20 years, I have had one failure and carry a spare - it's either that or reinstate the points - which makes it expensive but to keep a perspective, in the same period the coil has failed twice -

It's the same story with the Rover system


Over 35 years I have never had a set of points or capacitor fail, but I have had one coil start to become intermittent a couple of years ago. Many of those who convert to electronic systems recommend that a set of points and capacitor is carried as a 'spare'. Yes, electronic systems probably will remain consistent between (and way beyond, one of the reasons North American cars had electronic systems, and look what a pile of poo the Opus was) services but on a decently maintained car I'd bet you wouldn't notice the difference, and having all those bits to fiddle with every 3k is all part of the fun of ownership, isn't it? Since I have been using dwell as a measure of points condition I go many services before changing the points, or even taking the cap off, at least the 10k replacement intervals recommended. Before I used to get the dizzie out to check the points gap at each service so 'might as well' change the points at the recommended intervals. Another benefit is that a high-energy system *could* just make the difference between starting and not starting under very adverse conditions. It is very definitely NOT an investment.
Paul Hunt

Over 15 years - better starting, smoother idle - more consistent dwell. Less hassle than points. Ypou should be able to take the plug gaps out another 5thou, but no noticeable difference on the road.
I accept the problem if the system fails on the road, but so far so good.
Not an investment, but a labour saving device - like a dishwasher?
Dave Wellings

I fitted a "magnetronic" to my MGB (No longer with me) and I thought it was good. You have to saw the points mounting post off so you would need a whole other dizzy if you wanted to carry a spare.
It is only a points replacement so didn't help much with poor starting, etc, but did take the hassle out of maintenance. With points, I got fed up with the bedding in that happens when they're new, requiring re-setting after a few weeks.
ANother problem is that often rev counters won't work - it depends on whether you have one that connects directly to the points or one that use an inductive loop - the latter generally won't work.
T Green

i have fitted two sets of lumenition on my v8, both failed. first one after 3 weeks ( appx 100 miles) second at about six months(2000 miles)i now have an ALDON unit matched up to a sports coil now onto its 4 th year (20,000 miles plus ) and never missed a beat. worth looking at, quite easy to fit...........gerry

Chris - from reading the above I'm obviously not as technically minded or knowledgeable as some of the previous correspondents but I fitted the Performance version to my V8 seven years ago. When I bought the car I drove it 75 miles to my home and it packed up twice costing over 100 in call out fees to get it home. Each time the fault was put down to a dizzie fault of some kind. The first thing I did was order a Lumenition and have it fitted by an expert with rolling road facilities. Now I don't know if they are any better than the original equipment but I have never had one minutes trouble with it since; even when the car has been garaged for comparatively long periods. Some may disagree with me but for my part I would thoroughly recommend them even for the peace of mind that they give. If mine packs up I'll replace it with a new one.

I've been using a Luminition system for the last 13 years on my GT & would never go back to points. The only failure I had was of my own doing. I was reconnecting the coil "blind" & got the leads crossed. I feel there should have been protective diodes in the design to prevent this. However this is my only complaint & I would certainly reccomend one.There was a cheaper Electronic Ign. available in UK . It was called Pirhana or Baracuda. I don't know if it's still available, but I found this system quite reliable too.
Barrie E
Barrie Egerton

I've had a Lumenition Performance Ignition in my Factory V8 for nearly two years and it hasn't missed a beat. The Car never started particularly well when hot and still doesn't (after Weber 500) but the Ignition has been superb and the idle is rock stable and I have put 45,000 miles on my V8 in two years in all sorts of traffic and in three Countries. For a start I don't use the Lucas Distributor. I rebuilt mine and still found she didn't like to idle well at low revs, below 800 say (I like to run it low so the fans take longer to cut in). I did tests with my Mallory Dual Point distributor and found the Mallory a much better built unit. I didn't like the dual points after a while. So I removed the advance plate from the Mallory, expoxied the advance plate of the Lucas to the Mallory base plate and affixed the Lucas Lumenition Optronic Module. This works beautifully, unfortunately I lose vacumn advance but I don't miss it at all, doesn't seem to do much for my V8 whereas it is a huge benefit on the 4's. I've been doing 500-700 miles per week in my V8 for the last few months and never had a problem.

That said, I agree with Paul - a properly set up and maintained points system works just as well, is fun - give you something to play with. Especially with the neato external dwell adjuster on the Lucas. :) I got so bored with the reliability of my V8 I had to buy a midget to introduce a little bit of that missing fear factor - "oops did I leave my tools at home?". <VBG> ;)

If u want more info on the Mallory or the Lumenition it's in the archives.

74 V8
Neil Cotty

This thread was discussed between 04/11/2002 and 07/11/2002

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