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MG TD TF 1500 - electronic ignition review

I've been going through the archives on electronic ignitions. I should have the engine back this week and am wondering if this would be the best time to switch... if so,

Seems my choices are

123ignitions (nice programmable type but requires sending in the distributor, and quite pricey)

Any other versions I should look at?
What are the advantages/disadvantages between these options?

Thanks for any input...

Geoffrey M Baker

Crane with a Pertronix sensor.
Gene Gillam

Just on the Pertronix site trying to search for the correct igniter kit. They list kits for the Lucas DKY4A-40162A and the DKY4A-40162E

Mine is a DKY4A-40162F

Wonder what that means ...
Geoffrey M Baker

I run EI in only one classic vehicle out of the eight I own (not the TC). It's the only one to ever have suffered a complete, unrepairable ignition failure. That said, when they are working they do work well. It's just that you will have no warning whatsoever if things are about to fail.

I think you will find that most people who run EI in their classic will swear by the one they have. In reality I think they are all pretty equal. In my admittedly limited exposure I've seen more Pertronix failures than any other type, but to be fair there are probably more of them out there than any other. If I had to choose one for my own car, I would choose one that is invisible.
Steve Simmons

I have 123 in my Porsche 912 and I had a Crane in my Bugeye Sprite. I had a Pertronix in the Porsche briefly before getting the 123.

I really don't like the Pertronix. There are a lot of compromises in its design to make it fit into the small space inside a distributor. For one thing, there isn't enough cooling, and they are known to self-immolate if you leave them powered with the engine not running. I was happy with the Crane, but I had to make my own shutter for it, because the one that came with it didn't fit well, and I was worried about how that would affect the timing. Also, if you are worried about appearance, you will have to mount the electronic box under the scuttle or some such place. The 123 is expensive, but it's a beautiful unit.

People worry about reliability with electronic ignitions, but take a look at this (or any other) forum: the ignition problems people are having involve conventional points, not electronic systems. Electronics at their worst are more reliable than electromechanical things at their best.
S Maas

There are a lot of similar devices to the Pertronix available over here and usually much cheaper. Whether they are as good, or even better, I have no idea. However it strikes me that with this type of unit if you do get a failure its very easy to swop it out either with another identical unit or a set of points, and it wont cost a fortune to carry a spare either.
Dave H
Dave Hill

I swear by the Boyer-Bransden electronic points assist kit. If it should fail ( I have only heard of one) you simply swap 2 wires and reconnect the condenser and on you go. Much better starting and slow tick over.
Mine is stuck to the TF side panel below the rad strut and is nearly invisible.
The usual disclaimers, I just like the product and it is cheapish.
Ray TF 2884
Ray Lee

Geoff, before you go any farther - have you converted to a negative ground configuration? Bud
Bud Krueger

Ray. If I recall the Boyer Bransden kit has been around for many years and was originally intehded for motorcycles. It still uses the points but they pass only a tiny electric current, acting like a trigger for the electronics in a separate box. The point last much longer that way.
Dave H
Dave Hill

Yes Bud, I'm negative ground. Sorry, should have mentioned that :)
Geoffrey M Baker

I have a Pertronix in the TF... I doubt I would buy another. This is the second one.

Had points in the now departed TD. Didn't drive it often and several times I would have to file the points to remove the oxidation in order to get spark.

I have a Crane in the's been there for nearly 25 years...It would be my choice but it does have the external heat sink that I found objectionable when I went through the TF 10 years ago. I no longer care about the visual thing any longer and should the Pertronix crap out again that is where I will be headed. It's the gold colored unit center left but I believe the new units are now black...probably less noticable.

MG LaVerne

Alas I have no definitive answer. Just some observations on my supercharged, positive ground, 5-speed, roller cam TD.

Due to the oil seepage into the distributor and all the oil flying around in there, the conventional points got oil wet and messy and subsequent ignition issues. This required periodic cleaning and re-setting.

My Pertronix has been reliably but not as adjustable as the 123.

The 123 I received had some issues and required sending it back to Holland for repair. I have received it but not yet re-installed it. I think the big feature here is my ability to set the advance/retard curve with my laptop via a USB connection. I believe to treat my engine as best I can I want to retard the ignition when under heavy load. The curve can be set on the 123 to advance the timing as the RPM increase but to also retard the timing as the intake manifold pressure goes from vacuum to positive pressure.

It has been a very busy summer but I hope to re-install the 123 within the next month and experiment with it. I'll post when appropriate.

Mort 50 TD

Crane has the worst website, it's hard to figure out what unit(s) I would need for the TD. The Boyer-Grandson seems interesting but British (no offense, I just mean parts may be harder to replace over here) but their website is also a bit confusing as it is aimed at motorcycles, not cars.
So far, I believe that Crane may require modifications to their parts to work on our cars (shutter does not fit correctly?).
The 123 is out of my budget right now but seems by far the easiest and simplest install - just swap distributors...
Continuing the research....
Geoffrey M Baker

Boyer Bransden have suppliers in the USA.As for replacement parts there is only one and that is the unit.
As for replacement Brit parts, my 1955 BSA A7SS is still using its original Lucas bits. Mind you I have to adjust the voltage regulator every 5 years or so, and the magneto doesn't like getting wet ;-).
Ray TF 2884
Ray Lee

IMHO, on a freshly rebuilt engine, I would start if off with the (known) points setup,, If, per chance, you do have a problem with the new engine, you are just adding another unknown variable into the mix with the EI.. get it running and broken in first,,,, then mess around with the EI.

Just my thoughts,
Steve Wincze

Sorry, meant Mallory, not Crane .

Gene Gillam

Steve, that's my plan; I need to get the engine running first, but when that's complete I'll switch over. As you say, I don't want to add unknown variables. I'm just thinking now the engine is totally rebuilt, once running an electronic ignition might take it to a whole new level of reliability.
Geoffrey M Baker

"Electronics at their worst are more reliable than electromechanical things at their best."

With respect, I wholeheartedly disagree. I've caravaned tens of thousands of miles in T-Types, and only once has a points-equipped car had a problem when the 60-year-old condenser started to fail. But the car still ran. The only cars ever towed home were equipped with EI. Having the appropriate spare parts could have kept them running but the owners were very confident in the reliability of the units.

Usually when I hear about ignition problems, the end result is that there was either a major fault in a related system (bad ground, improperly adjusted regulator, etc) or the owner had done something wrong. Outside of that, faulty components can be to blame, as with the batch of bad rotor caps a few years ago. (This will affect Pertronixs as well) Or the classic one, worn out distributor bushings causing timing or spark issues, at which point someone will "fix" it by installing EI rather than rebuilding the distributor. Or in Mort's case, oil being blown into the distributor and onto the points. That isn't a reliability with the ignition system, it's a separate issue in a related area that should be remedied.

EI can be as reliable as anything, but in a T-Type there are so many variables that it will never be as reliable as in a modern car. Heat, vibration, voltage fluctuation, current resistance, old connectors, exposed components, etc are all hard on electronic components. I've had pretty good luck with the one EI-equipped M.G. that I own, outside of the control module frying once because of a careless body shop guy. It's a Luminition unit by the way. Seems high quality and has worked well over 20K miles or so.
Steve Simmons

Geoff, you need to take a little closer look at the Pertronix catalog. The LU-146 is for the distributors with suffixes E thru Z. Your cam would be fine. I've been doing a learning curve with the Pertronix LU-146LS for almost a year now. The LS stands for Lobe Sensing, it doesn't care about the shape of your cam. It doesn't have a magnet collar that raises the rotor. Installing it requires a 'modification' of the points plate. The smart thing is to install the module on a new points plate and put the old one in the toolbox to satisfy the 'what if' issue. A significant issue is that the LU-146LS does not want to operate with hardwire ignition cables, and suppression cables are not readily available. I made my own. Except for the carbon brush issue from the magnet collar (see ) I have had no problems with a Pertronix ignition in over 15 years of use. It would take me about 5 minutes to reinstall my original points plate and be running. Bud
Bud Krueger

I have run first the Crane, then the old Pertonix for many years with no trouble. At initial installation the car immediately ran better and consistently. With points, as the rubbing block wears and they arc/burn, the dwell angle and subsequently the timing gradually changes. Not so with electronic. One of the three times the car was towed home was due to a broken points rubbing block. Read the horrifying article on condensers (and as fabulous article about how ignition works) - "Conventional Ignition Systems" in the new issue of Totally T-type. George
George Butz

I guess my clubmates are just the lucky ones then! Me, I check my points twice per year and they are usually within a couple thou of spec. Rapidly wearing points blocks are usually caused by a lack of lubrication. There is supposed to be a special grease on the spindle to lubricate the block as the dizzy spins. Most of the dizzys I see are running bone dry. It's amazing they hold up as well as they do.

EI is good stuff in the right situation, but in all honesty you shouldn't notice ANY difference between a perfect points setup and EI on an otherwise stock T-Series MG. But most people's cars have less than an ideal ignition system, and the one thing EI will do is mask numerous problems that points will not. So there is often an improvement after the change. This is why many people recommend getting the car running perfectly on points and THEN making the change to EI if desired.
Steve Simmons

Let me start by saying that I had two Vodka and tonics with supper at the local Pub.
Since this thread is slowing down and this avenue has not been mentioned let me jump in.

I think that all the systems mentioned are "Old Hat". The automotive world has moved on.

If you want something that looks original dont read on.

Here is my plan for the future and I have mentioned this before.

I feel the XPAG engine should produce around 88 HP.
I get there in the following way.

My 1961 1500 OSCA produces 125 HP @ 6500 rpm. 125*(1250/1500)*(5500/6500)=88
So what to do? I think Intake and ignition need work.

The coils are a constant problem. I had my original Lucas burn out. The rotators are a constant problem. Getting good ones is more of a problem. The distributor caps are an issue. The spark plug wires radiate electrical noise and interfere with modern electronics.

Modern cars have moved on to multiple coil, distributerless ignition.

Once I get my TD fully checked out and some miles on the existing system I fully intend to convert to a Coil-on-plug system.

I will need to incorporate a TDC sensor and pickup into a new pulley. All timing and advances will be handled by the computer and the distributor will be a thing of the past. This will be months or a years in the future but I believe it will produce a performance improvement.

Remember each coil fires only once every 4 times each piston reaches TDC on compression so the time to build up energy is increased by 4 times over the present system. This should give a hotter spark and much longer coil life.
The wires going to the COP's are lower voltage so there is little RFI. All advance is programmable and can be set an a Dynomometer.

Coupled with a reworked head I think you could see a big improvement in performance and reliability.

Just my thoughts

Jim B.

Jim B in NJ

Guess I'm the lucky one, Steve. About 15 years ago the late Skip Kelsey recommended the Pertronix system to me. I've had great results since then. As a retired EE I'm fascinated by the Hall Effect application and its simplicity. It's been a relief not to have had to fuss with the OEM points system. My backup is still the points plate that I removed 15 years ago. Bud
Bud Krueger

I wouldn't call it luck, Bud. In a well maintained system I don't see why electronic ignition won't last as long as anything.


"Modern cars have moved on to multiple coil, distributerless ignition."

This reminds me of something. What could it be? Oh yes, my 1925 Ford truck! But it gets only 22.5 HP from 3 liters so surely multiple coils and distributorless ignition robs power! ;)
Steve Simmons

I thought they had a single coil with vibrating points, I think called "constant ignition" and still used a distributor but no points on the distributor.

I have a coil. It can start anything.

Jim B.
Jim B in NJ

I also have Petronix from Skip Kelsey in the TD. Had it in the MBG until I put the coil wire on wrong and fried it. I needed to get the motor running, so switched back to points. Using the points, condensor, plate rotar and cap that Jeff at Advanced Distributors puts together for the B.
Bruce TD4139 Cunha

Some mid-70s Mercury outboards had separate coils with some type of under the flywheel mounted trigger. They would fire surface gap plugs (no side electrode) perfectly in the oily two stoke mixture. No clue why it took so long to be adopted for cars. George
George Butz

The pertronix unit I bought 8 years ago has given me no trouble what so ever in 8 years... That is because my points condensed system that has taken me all over the continental U.S. Has been performing so well the pertronix is still in it's original packaging on the self in my parts cabinet at home.

Regards, tom
tm peterson

Hi Jim, they use one "buzz box" per cylinder. There is a timer to distribute spark to the plugs, which is sort of like a distributor. Basically a metal lid that goes over the front of the camshaft with a flapper inside riding on the end of the shaft itself. Rotating the cap via mechanical rod adjusts timing on the fly.
Steve Simmons

This thread was discussed between 12/08/2015 and 13/08/2015

MG TD TF 1500 index

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