MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - Original Dizzy & Electronic Ignition

Been through the archive & most of the posts on point (no pun intended) are at least 10 years old & don't really address my queries below. I want to fit an "invisible", mapable, electronic ignition into my original dizzy with NO external indication that it's there! I want to keep my + earth & would like to fit it myself. (I'm intending to install a Fanelli cam). Is there a kit available that someone on this site has installed? What is it called, where is it from, how difficult is it to install, how much does it cost & does it work? Does the Crane XR 700 satisfy my wish list? I eagerly await detailed & informed replies!TYIA. Cheers.
Peter TD 5801
P Hehir

I can't answer the electric conversion and I admire your desire to keep the car looking original.

If originality is your quest and you want your distributor curved to match the performance enhancements of your engine, why not send your original to distributor to Jeff at Advanced Distributors?

I was very pleased with the service he has done and so has many other people.

Call and speak to him about your project.


Advanced Distributors
17495 Marystown Road
Shakopee, MN 55379
(612)-804-5543

email jeff@advanceddistributors.com
Frank Cronin

Jeff is great and he recommends points. I personally prefer the points as I have heard of so many pertronics failures. A set of points is road serviceable. The only reason I would want an electronic ignition is for the rev limiter. Otherwise I prefer the road serviceability of points.

Alex
Alex Waugh

Thanks Alex for your thoughts. My dizzy is fine but I wanted to get the best out of the new cam & reasoned EI was the way to go. There doesn't seem much in the way of control in the old type of dizzy in terms of re-curving for the optimum performance throughout the rev range. As ignition advance & retard is just by a very primitive set of weights & springs, where, how, what is the fine control that a re-curve is supposed to bring? More weight, less weight, stronger/weaker springs? The only other thing that is adjustable is the points gap & surely that is what it is? I don't have a problem cleaning, adjusting or replacing points. I just want to get the best out of the old girl & ensure she has a long & happy life. I have been advised that EI is the way to go. Can somebody convince me either way? Cheers.
Peter TD 5801
P Hehir

Peter,

These people put the 123 ignition into the original distributor, not cheap but the 123 gives you 16 advance curves to select from. The site mentions that they can provide either positive or negative earth devices.

http://www.123ignition-conversions.com/makes-types.html

John 52 TD

J Scragg

Peter,
IMHO, From what I have read about possible failures in the electronic ignitions, keep the points that you take out to use as spares when the electronic unit fails,,,

SPW
STEVE WINCZE

Peter,
I have a 123ignition conversion fitted on my TD, as it is a standard engine I use the standard curve. I have used points and petronix previously but find the 123 conversion out performs both. I am very happy with the performance the car starts on the button and revs freely through the range. I have now driven 4000 trouble free miles and it has never missed a beat.As the system is built into your original distributor you cannot tell it is there till you take of the distributor cap and with 16 possible advance curves you will be able to set it to suit your car.

Hope that helps Chris.
C A Pick

Chris your experience is pretty much what the scuttlebut is here. It was the 123 that was recommended & I've also just discovered the Crane XR 700 is very obviously visibly not original. Noted your recommendation Alex & took your advice Frank & emailed Jeff. This is what he had to say;

"There is NO electronic ignition kit that will work well with your distributor. The copper core plug wires throw off an EMI and RFI field that WILL disturb an electronic ignition's signal. Run points
until you exceed 50 hp per cylinder. Jeff.

Decisions, decisions...

I've already sent an email to the mob that supply the 123 that John suggests & am waiting on a reply. Chris. Can you email me offline pjbm@bigpond.com & perhaps forward me any other info about the 123 that you may have? I'm leaning in your direction but Jeff's comment has me worried. Wonder how people get on over 200 hp? Maybe replacing the plug leads with black shielded wires may solve Jeff's issue? Anybody else running the 123? Cheers.
Peter TD 5801
P Hehir

Peter,
I have a TD with positive ground. I have had both the standard and electronic ignition(Petronix). I have on occasion switched them around to resolve one issue or another. You must be careful when switching since the wiring is different. Under advice from Jeff and others I am now using the standard points.

Have you considered Len Fanelli's roller lifter cam? The whole mechanical idea of getting away from a flat lifter in favor of a roller lifter seems to make sense. I just installed one and you can not tell the difference from external appearance. Although new to me the performance of the cam and lifters(also push rods and springs) seems excellent. It doesn't seem like the same engine. It just rev's so easily and smoothly and with more power. I am not familiar with the Crane cam but if it doesn't have roller lifters I personally would not consider it.
Mort
Mort 50 TD (Mobius)

Jeff supplied me with a modified replacement distributor to replace my junk one. I'm a fan of electronic systems when trying to get better performance. Here's What Pazon (from Bay of Plenty) has to say about RFI and how they mitigate the effects for the system they provided for my Norton. They only supply motorcycle systems to my knowledge.

Important notes:

5k suppressor/resistor plug caps (as supplied) should be used with this system. Resistor spark plugs can also be used. Attempting to run the system without any suppressors will result in excessive radio frequency interference (r.f.i.), which may cause misfiring, bad running, loss of ignition and interference with other electronic/electrical items.
For reliability, copper or steel plug wires (h.t. leads) should be used. Carbon fibre plug wires should
be avoided.

Interestingly the analogue system I used on this and other bikes apparently had no such issues. The advance curve, however was more of a straight line advance rather that the very tailored one possible with the digital system.
JE Carroll

Yep Mort. Thanks for your post. See my initial post above. "(I'm intending to install a Fanelli cam)". The Crane XR 700 is a dizzy not a cam but doesn't look original so I'm not interested. Jim, I received the following reply from Erik Frenken who works for the German manufacturer of the 123 EI. His answers to my questions are in brackets.

"Can I use my original Lucas sports coil? Originality is most important to me!
(As long as it has at least 1.5 ohms resistance in the primary windings it's okay. But we have made the experience that old coils don't work as good as newer ones).

Can I use my original black ignition wire set?
(Yes, but copper wires tend to interfere with our electronics. The better choice is carbon wires with silicone insulating.)

Are yours specially shielded to prevent interference?
(Yes, see above).

Do they look exactly the same as the original black plug leads & caps as fitted to the MGTD? Originality is most important to me!
(No)."

As you will see it seems we are in disagreement again. Your posted recommendation from the Kiwi mob "For reliability, copper or steel plug wires (h.t. leads) should be used. Carbon fibre plug wires should be avoided" is totally contradictory.

By the way Jim just correcting a geographical error from the other thread. No disrespect intended to you or the Kiwis but calling an Aussie a Kiwi is a bit like calling a Canadian a Yank. (Also the Bay of Plenty is in New Zealand & I live in Sydney Australia).

Seems there are quite polarised views on the subject of EI's. However as he has no vested interest I am swayed by Chris Pick's first hand experience & I think I will spend a few bob & exchange my spare distributor body for an EI (in an original body) & make my own evaluation. If I'm not happy I can easily go back to points. Cheers.
Peter TD 5801




P Hehir

Peter - It appears that originality is your first concern - TOTALLY original in appearance -and strong, trouble-free spark comes next.

I know I'm just one guy, but I would recommend a rebuilt Jeff Schlemmer distributor for which you tell Jeff what your car has in the way of performance mods, so he can set up weights and springs to match. Then I would put on a BR12 coil (the original hi-po T-series coil), and run with points. The Lucas Supersport coil is NOT original to the car.

That way you can have stock dizzie, stock copper-core wires and the proper separator, all stock fittings and fasteners, and a strong spark. I supplied a BR12 coil to a Mark II owner last year, and she reported that the car had never run so well in the time she had owned it.

There is a compromise with every change from original, be it looks, wires, performance etc., so stick with stock. You'll clean and adjust the points once every year, carry a spare plate with new points and condenser and rotor (Jeff again - the red one), and be done with it

My opinion.

Tom Lange
MGT Repair
t lange

Tom can you email me a pic of the original BR 12 coil as I'd like to compare it to the one fitted to my car & my 2 other spares? Cheers.
Peter TD 5801
P Hehir

Peter - Here is a picture of the original coil from my '53, but I have no idea what BR12 means. It has 952 stamped on the end which I assume means September 1952. Note that it says Lucas on the top. I'll post another picture with the new Moss reproduction.

Joe


Joe Olson

...and here's the new Moss coil. It lacks the Lucas label and has the bracket in a somewhat different position. Otherwise they are identical in appearance.

Joe


Joe Olson

Thanks Joe.
P Hehir

I'll dig out a BR12 tonight and send a photo - it looks like the stock Q12 but just a bit fatter. It's the coil listed in Section R, the Mark II supplement to the Service Parts list.

It's the original equivalent of the modern Lucas Supersports coil.

Tom Lange
MGT Repair
t lange

Thanks Tom.
P Hehir

Peter, My sincere apology, I thought sure I read NZ, hence the Kiwi reference.

The Pazon folks do recommend copper or steel with their resistor end for RFI suppression. Carbon wires would accomplish the same thing so I suspect, but don't know for sure, that they don't like carbon for a motorcycle application, especially a Norton Commando, because of all the flexing. The Norton coils are rigidly bolted to the frame but the engine is mounted in rubber and really moves around a lot. The wires are also out in the turbulent air as well.

That's all a guess but my point was that it seems digital electronic ignition systems are subject to RFI that can be mitigated, not a wire recommendation. I would think you would be able to either use a resistor type plug, carbon wires, or resistor plug terminals to make a programmable digital ignition work and keep a near original appearance.

I discovered that the early analogue system I fitted to my E-start had a serious flaw. Under low voltage conditions it would fire at full advance, locking the starter sprague. When that happened I wished I had kept the Lucas points!

Again,I apologize for the mistaken nationality.

Jim

JE Carroll

Apology accepted Jim. In terms of the carbon v copper leads I'm as confused as ever! Clearly the manufacturer of the EI says "copper wires tend to interfere with our electronics. The better choice is carbon wires with silicone insulating" while on your earlier post you quoted Pazon as saying "For reliability, copper or steel plug wires (h.t. leads) should be used. Carbon fibre plug wires should be avoided". In your later post I don't understand what you mean by "not a wire recommendation"? I really struggled with your third para.

The problem is twofold as I see it, RFI (Radio Frequency Interference) & EMI which I assume is Electro Magnetic Induction. I know from my time as an Instrument Fitter in the RAAF that current travelling through a wire induces a magnetic field as well as stray or back EMF's (Electro Motive Forces). Clearly both of these, along with the radio waves that are all around us, are the problem as identified by Jeff & also by the 123 manufacturer. As it's his bit of kit I'm inclined to go with his recommendation. If I can find 7mm black silicone insulated carbon leads that look original then I'll give them a go. Because of the wildly & widely differing opinions I guess it will simply be a case of suck it & see. I'm still some ways off from firing her up as I'm waiting for the Fanelli cam to arrive before I can begin the final reassembly. I then intend to fine tune her on a dyno with the EI. If there are problems I'll just refit the reconditioned dizzy I have on the car now. I'll also look into finding someone local who can fiddle with the weights & springs based on my existing compression (about 10 to 1), carburation, 1"1/2 exhaust & the Fanelli cam. Tricky stuff! Cheers.
Peter TD 5801

P Hehir


Peter - You cannot use carbon wires with original-type distributor cap connections. The solid-core strand wires need to be exposed and splayed over the brass washers, to ensure a solid contact. (The WSM and owner's manual show this most clearly.) Carbon wires just won't work, and they will easily pull out of the distributor cap with little resistance.

Since original appearance is a primary concern to you, that rules out the carbon application - with carbon wires you would have to use a distributor cap with push-in ends and rubber boots, quite unlike the original screw-in terminals.

Tom Lange
MGT Repair
t lange

Peter,

"There is NO electronic ignition kit that will work well with your distributor. The copper core plug wires throw off an EMI and RFI field that WILL disturb an electronic ignition's signal. Run points
until you exceed 50 hp per cylinder. Jeff.


My point in all of this is to offer that RFI can be mitigated without resorting to carbon wires. Pazon recommends either their resistor ends or resistor spark plugs. If total original looks are important and Pazon are to be believed, resistor sparking plugs would be hardly detectable. You could use the original distributor cap with the screw-in terminals. A conversation with 123 concerning resistor plugs may confirm if it's feasible. Resistor ends would be obvious and carbon wires not easily workable, as Tom points out.

Par 3 is only related to the sad unintended consequences I found when fitting an early electronic ignition system to an old bike. It ran better but ultimately broke it. When that happened late at night and far from home I wished I had kept points. In the process of re-restoring it I was going to put the points back in but some time in the intervening 20 years they and the advance mechanism have gone missing. Casting about for a better system I found Pazon and Tri-Spark, from your neck of the woods. Both of whom have solved the low voltage, full advance issue that caused me grief. This has zero to do with an MG other than to agree with others that when points break, you can fix it at the side of the road.

Jim

JE Carroll

Thanks Tom & Jim. I have had to previously replace plug leads Tom. I splayed (& soldered) over the brass washers but have no experience with carbon leads. The thought crossed my mind that it may be possible to use a suitable adhesive to secure the leads to the original cap in conjunction with Pazon's resistor plugs. Seems my only other options are to explore the resistor plugs from Pazon, both with them & the 123 manufacturer or to try & find a better shielded black 7mm copper HT set that 123 are happy with. Of course I could do what Chris has done & just run with the original leads. He advises offline he has had no problems. Appreciate your advice guys. I'll post any further results. Cheers.
Peter TD 5801
P Hehir

Just to add my experience to the debate. I have run an ignition 123 electronic ignition, fitted to my original distributor for over 3 years and 4000 miles. I have used the original spec distributor cap fitted with copper wired bumble bee spark plug leads screwed directly onto NGK spark plug caps see photo.

I have never experienced any problems the car always starts on the button immediately revs freely throughout the range never missing a beat. I also have a 5 speed gearbox fitted and have regularly driven for over 3 hours non stop on our motorways cruising at 65mph at around 3500rpm. The car runs like a dream. I do not profess to be an expert in the field I am just giving you the facts from my experience of running a TD with the system as described.

Cheers Chris


C A Pick

I have the pertronix Positive ground on my TF and Bumblebee stranded wire all with original wire end plugs.

To solve the RFI spark noise from the plugs, I use Champion RN5C resistor spark plugs.

Otherwise the spark gaps make for an amazing radio transmitter covering a wide range of frequencies, juts like the early CW radio transmitters.

My Dad made his first Ham Radio transmitter with a Ford Model T spark coil and spark gap in the early 1900's

Note also that your generator is also a good source of RFI noise.
It can be suppressed by a capacitor so you can use an AM radio in the T Car
Don Harmer

Pazon plug caps may be NGK labeled for them.

http://www.ngksparkplugs.com/docs/resistor_covers.pdf

Don's successful use of resistor spark plugs may be the answer for the original look. I doubt few will fault you on the choice of spark plugs.
JE Carroll

Thank you gentlemen. Now were getting somewhere! I feel much more confident about my plan to go with the 123 EI. Regards.
Peter TD 5801
P Hehir

As promised:

151248970374 eBay - a BR12 coil. Looks like a Q12, but smaller.

Tom Lange
MGT Repair
t lange

Sorry, I MEANT to say that the Q12 is smaller.

Tom
t lange

Tom, Joe's pic above of his original coil is the same as the one listed on ebay, which you've identified as the BR12. Cheers
Peter TD 5801
P Hehir

This thread was discussed between 12/03/2014 and 15/03/2014

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.