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MG MGB Technical - Electronic Ignition Prices

Hi All
I had a bad experience many years ago with electronic ignition and have used points since, I was thinking of trying electronic again [and keeping points in the glove compartment!] but was surprised at the variation in prices, ie from not much more than 20 to well over 100, is there any great difference between them or is it a case of the suppliers hoping that some people will only buy something if it's expensive?
The unit that failed on me was a well known brand at the time.
R. Algie

I've used Lumenition on my race cars over the years and never had any problems with them. Having said that, they are a bit pricey these days.

I've heard bad reports about the 'Ignitor' units, but have never used them myself.
Dave O'Neill2

I don't have a whole lot of experience, since I have kept purchases limited to 'time tested' equipment. I suppose some of the earlier electronic systems may have suffered because of componenet failure, not design fault. Now-a-days, components are really quite reliable. In your case, maybe you want a system that you can easily change back to standard at the roadside for piece of mind? There are many about. Do some perform better? marginally I suppose. One could say that the standard system, well adjusted, and in tune will be no worse that an electronic system. The point being that the standard can go off quickly. Some may pack a real spark punch, to as it were, burn all the mixture. But, Maybe the mixture was too rich in the first place? I have a 123 system, have had no trouble since the day it was installed, and it just went in and started. But it is expensive. I also have to carry the complete old distributor with me, and it is a little more involved if I have to swap things back at road-side.But, I like machines, I like tecnology, for me this was the right move. Mike
J.M. Doust

The old saying that you get what you pay for certainly works......!

I purchased one of the cheaper versions, just to give it a go as I wasn't 100% convinced, and, whilst it is NOW sort of working, the trouble that has been put into getting it work was dubiously worth it, and certainly should decent condensors still be available, then I would say not!

Having said that, I am now a bit more convinced about the megajolt system, but I fear that poor Mr Burgess may well get a visit to set up the 1-2-3 that he sells, now that you can get a fully mapable system (just hope that it works with a Mac!)

I have had the Powerspark system from fitted to my daily driver for the past two years. 22,000 miles so far and not a single problem. With the easier starting, smoother tickover and reduced maintenance it is definitely a win. It only takes 20 minutes to fit and can be changed back to points if that's really what you want.

IMHO it's the best 28 you could spend on your B.

I've previously used the more expensive Petronix / Aldon Ignitor units of my previous B's and they've also performed faultlessly.

It was an 'expensive' one that failed on mine, it was just over 10 years ago so maybe things are better now, the alarming thing was it had been fitted for several years and had done thousands of miles without any problems and then it just packed in completely, one minute I was driving along the road, next I was parked at the side with the car dead as a doornail, no warning whatsoever, fortunately I managed to coast into a layby. It was quite an alarming experience as I could have been in a lot worse place when it happened.
I will probably try a Powerspark [with a set of points in the glovebox] as the points are due to be changed and they do seem to run and start better on electronic ignition.
R. Algie

I fitted a Powerspark from a couple of years ago and it didn't work. That was replaced by a working unit which a few months later embarasingly failed on the MOT ramp. I then fitted another unit from MGB Hive which looks identical to the Powerspark unit and for the past year and a half it seems to be fine. Just lets hope it keeps working. As already said at 28 it is good value for money provided that it lasts.
Iain MacKintosh

"then it just packed in completely"

That's exactly what electronics do! And fail completely, so they must be replaced before you can make further progress. At least points can usually be tweaked to get you going again, and relatively easily replaced at the roadside if something on them has broken.

There's been several complaints in the Sunday Times lately about the electronic handbrakes fitted to some cars playing up, and needing several goes before it would let the car move, with one person asking "Just what problem is the electronic handbrake trying so solve?". To which someone responded that he didn't know why all cars didn't have electronic handbrakes by law, which give hill start assist, as "hill starting without them is such a difficult and dangerous manouvere". Someone who should never have been given a licence to drive, I suggest. These so-called driver aids are getting ridiculous. A bloke in a BMW backed into my daughters car in a Tesco car park the other day say his reversing sensor didn't tell him that someone was there. So what's suddenly wrong with looking out of the windows? Is that difficult and dangerous as well? Aid to incompetence more like. He then proceeded to drive out the wrong way through the one way system.
PaulH Solihull

My Passat had an electric/electronic handbrake. It was quite useful sometimes, but it did play up, too.

I used to get warning messages about a 'parking brake' fault. When it was serviced, I asked the dealer to check it out and they said it was a faulty switch - 90 including labour. As I had already discovered from a VW forum that the switches often failed, cost 26 to buy and took 2 minutes to replace, I declined their kind offer.

Another problem is that in order to replace the rear brake pads, you need the VW software to withdraw the handbrake mechanism in the caliper. Coupled with commonplace motor failures, resulting in caliper replacement at great expense.

There's a lot to be said for a hand-operated lever and bowden cables.
Dave O'Neill2

Did anyone that used the Powerspark system change to a 12v coil as recommended in their ad?
R. Algie

I used the full kit as supplied by their double ... there was nothing wrong with that as such, but, the rotor arm, after about 100 miles, was badly worn on top, and it had been "bouncy" for those 100 miles.

There was also one in one of the midgets, and this has also not been in for very long, however, the wire has "chaffed" and there is no insulation - again causing alot of bouncing. Again, this has only been after a very very short mileage.

Since we have gone all anti-electronic all of a sudden, I have to report that some competition AIR GUNS have electronic triggers! I have never used them and since handguns are banned in the UK, it is of academic interest. Usually problems occured because the battery was low on 'juice'! Interesting my parents have a Hyundai i45, not sure if these are in the UK? Very nice but entirely keyless entry and keyless ignition. You just have to have the transponder somewhere on your person ( Anywhere!) and only you can get in and start the car. But what happens when or if the battery becomes flat? I found out. The doors are in the open state! Anyone could get in. They cannot drive off, won't start, battery dead. You can manually lock the door with a little secret key. I gather Paul you are not keen on electronics. You appear to be quite scathing of electronic ignitions? Trouble is electrics are on the increase. Remember the GOON Show, Eccles says, 'I got an electric Twit for Christmas.' That was many years ago. We are all going to see this more and more. Mike
J.M. Doust

I think it is more about how when electronics fail, there is little or no warning and nothing that we can do to "bodge it to get you home". With much of the older "technology", we were able to do just that. However as most people nowadays have no knowledge or interest in the mechanics of their car, being unable to fix it is of little consequence. (And MOTing vehicles with some electronic handbrakes is a nightmare too!)
Michael Beswick

The thing that seems obvious to me is that it's mainly aftermarket electronic ignition units that fail, I've never had a 'modern' car one fail and neither have any of my aquaintances, I've no doubt there will be someone out there who has but it seems to be pretty rare, it's certainly not rare on classics if other forums are anything to go by, maybe the problem is quality rather than the fact that they're electronic which goes back to my original question are the expensive ones any better and from my past experience the answer is no, maybe I'll just stick with points :)
R. Algie

We regularly replace "coil packs" on moderns. But the cars generally do normal annual mileages.

Not quite an ignition trigger but related!

Funny how we used to put the coil on the inner wing metal to keep it cool, and now manufacturers put them directly above the plug on the engine.......

In relation to your original question, I have Petronix Ignitor and it seems fine. FWIW I bought mine from the US (tho shipped from UK) several years ago. It may no longer be the case, but the US seemed to have a more bouyant home grown manufacturing base with less stuff being imported from places with dubiuous quality control. It was also miles cheaper with the exchange rate than the equivalent Aldon.
Michael Beswick

"all of a sudden"?

Not here matey!
PaulH Solihull

"it's mainly aftermarket electronic ignition units that fail"

Likewise it's 100% aftermarket electronic ignition units that work without problem. ;-)

Dare I add this is a "pointless" debate?

'Dare I add this is a "pointless" debate?'

You're contribution certainly is.
R. Algie

The 45DE4 factory electronic ignition was well known for premature failure, often within the guarantee period. It's official name was "OPUS", it was soon dubbed "'opeless". The 45DM4 factory unit that succeeded it is still extremely reliable, the module being used by dozens of manufacturers on hundreds of models.
PaulH Solihull

@ Ron

Sorry you feel my contribution to your thread was pointless, as someone who uses their MGB regularly I offered up my honest opinion on electronic ignition for the MGB as you asked.

My later joke, which seems to have gone above your head, refers to the fact that no MGBs were fitted with electronic ignition from the factory, ergo all electronic ignition units fitted to MGBs are therefore aftermarket.

Over the past ten years I've managed tens of thousands of miles on electronic ignition fitted to my MGBs without any maintenance required at all. I'd never have managed that on contact breaker points.

Good luck with the contact breaker points, I'll never return to using them.

Touch wood, I have had many years of fault free service from my electronic ignition.

I bought my first B in 1980. It was a 1966 roadster. Very soon after buying it I fitted electronic ignition and an electric fan. The ignition was Mobelec Magnum and the fan was taken from a Renault 16 in a scrap yard and operated by a Kenlow thermostat.

After many years of chasing rust, in 1992 I sold my first B and repalced it with a 1974 car that had just been brought back from southern California. Before the '66 car left I removed my "improvements" and imediately fitted the Mobelec Magnum to my new car.

However, you can no longer buy Mobelec Magnum.
David Witham

No MGBs were fitted with electronic ignition from the factory? All '75 and later Bs, at least the ones that were imported into the U.S., came with it as stock. As Paul stated, the early system was prone to failure, while the later system is near bulletproof. I've been running a distributor, based on the later design, for over a decade with no problems whatsoever. RAY
rjm RAY

It *was* only North American spec cars (which became the standard for all export models eventually) that had electronic ignition, ditto charcoal canisters, air pumps, single Stromberg carb et al. The reason was that at that time cars were expected to run for 50,000 miles without any interim adjustments, only routine replacement of service components. Points would never run for 50k, and presumably opinion was that they wouldn't run for 10k either. But the last set of points I had in my roadster did maybe 15k without any adjustment, staying within the tolerance for dwell all that time. The V8 did a similar distance but did require a couple of small tweaks as the 35D8 has a smaller tolerance for dwell at +-1 degree as opposed to the +- 3 degrees for the 24D4 and 45D4. I deliberately left the points in just to see how many miles they would do, only changing them when I noticed the roadster taking a little longer to fire up after a couple of weeks not being used. The V8 started the same as always, but I changed them at the same time anyway. The V8 plugs did 25k before I changed them, when hot starting suddenly became more difficult, but that's another story.
PaulH Solihull

Thanks for the clarification Ray. Maybe it's this early experience that's soured some owners into believing that all electronic ignition is evil?

It was the fact that points based systems had were rapidly becomming obsolete on new cars from the seventies onwards that persuaded me to give electronic ignition a try. I remember fitting a hugely expensive Sparkrite SX200 to an old Ford Escort I owned. It died prematurely in a cloud of acrid smoke, but the car definitely worked better before its demise.

CB points are lovely and I'm glad they're remembered with such fondness, but my personal experience of them failing due to little more than Autumn dampness whilst an attractive young lady sat in the passenger's seat of my very first car (1966 Austin 1100) waited patiently for me to get her home safely will live with me forever. Despite my misguided conversion to the new-fangled eclectrickery, I still live in those times. Sadly the attractive young ladies of the day have moved on with the years.

To enter the debate, my first B was a '79, came with an electronic dizzy. As we all know it's folly to be hard and fast about what/when when it comes to what the facrory did!! ..............."Hey Alf we aint got no CB dizzies". "OK Bert, we've got a few electronic efforts on the shelf, we'll use them!"
Allan Reeling

"I remember fitting a hugely expensive Sparkrite SX200 to an old Ford Escort I owned."

I built a Sparkrite 1000 from a kit in the 70s, never found it made any difference. Took it off when I changed the car, but never bothered refitting it. Still in a bench drawer, which has been in more garages than the unit has been on cars ...
PaulH Solihull

I fitted the Aldon 'Ignitor' together with their Flamethrower coil. Easy fit, never had an issue in 20000+ miles. Cost was 62 back in 2005.
A Riddett

I've been running with the 45DM4 for ten years without a single problem.

The 4 pin modules found inside the amplifier unit can easily be swapped out for high performance "race track" modules. I've seen some modules rated at 7 amps.

That means you can safely use a 40,000 volt coil with a 1.5 ohm primary and then open up the spark plug gap to .040".

Keep an eye on ebay, most people do not bid on these units so you can get them cheap.
Steven Rechter

After the expensive Pirhana and Jolleys "Classicheads" failed on my car I went for a Boyer Bransden assisted set up. It was less that 35 delivered and has given no problems at all over the 3 years its been on. I have an external capacitor on the car as well, out of circuit but i can change over to it by plugging the spade terminals at the roadside if i need to.
i was always happy with the Lucas set up , but the current crop of capacitiors from China you get from all the vendors now are frankly rubbish.
Stan Best


I experienced two type of electronic ignition with my Brit. Cars.
First is pertronix which do a fine jod for 4 years, and a 2-3 wires modif. to return original.

Second: Capacitive discharge ignition fron a US co. named Tri-star. They offered a DIY kit model SST which keeps point as a triggering device, but poinst last for years witout pitting. And a more sophisticated one Tiger 500 using points or any other triggering device (Halls).
Basic kit were extremly efficient to start my B-GT at -30 F with two weak batteries and slow cranking, which was not possible frequently with points.
To return to original set-up: reverse a plug or a switch.


Jean G.
Jean Guy Catford

This thread was discussed between 15/04/2012 and 05/05/2012

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