Lumenition Ignition

[Greta]

Ok - In the drive for performance and reliability - Ref Historic Rallying and RBRR - what do the team think?

Scrutineers reliably inform me that I CAN move away from points to electronic ignition and still remain within the regulations of post historic (H2 / Cat. 2 )  rallying provided I use the optronic and not magnetronic system - as Luminition WAS available in period as an after market tuning option.

So Ref use of such in a GT6 MKII what are the comparative pros and cons of either the Standard Lumenition Optronic system vs the Performance Optronic system - ( high revs in 2nd gear on tests - but otherwise normal driving with some high speed cruising. )

Particularly interested in the experience of those that have used such. Are they compatible with the mechanical tacho-drive my current Ex TR6 USA Spec Lucas Dizzy has?

[TedTaylor]

Forget these electronic whatsit's that fit inside the dizzy.  I had a Magnetronic (effectively same as Optronic) fail on Woody for no apparent reason after only a few year's use - and I think that is the reason why Phil's Optronic? ignition on his 4A was playing up and was changed over to points.

In my case I reverted to points and fitted a low mileage (30k miles) dizzy so that wear problems were not present and it went as well as with the Magnetronic which had been used for about 15000 miles.

While people say always carry a spare points set up in case your electronic set up fails - what is the point (:-O).  If the electronic fails at an awkward moment you still have to get out and change it ..... in the middle of a rally .......? 

One of the reasons that people give for the change over is for reliability and lack of servicing.  While this is true in that points must be adjusted periodically and changed every few years (with decent quality ones) over period of years points probably wins out. Especially as often happens that the lifetime of an electronic system appears not that long.

If you are going to go electronic then do it with a complete unit like a 123 ....... though this does not help if constricted to period systems by regulations.  It is the same reason why electronic systems in modern cars work reliably - they were designed for it from scratch, not add on bits.

Also don't forget - we oldies lived with points systems for many decades which included rallying and racing - and survived! 

 

MUT

[Greta]

Thanks for your views Ted -

I need to do something as I think my Dizzy Cam Lobes are worn - the peaks and the heel of the points only just meet. I've been trying to source a serviceable Lucas 6 cylinder dizzy with mechanical tacho-but so far no luck ( see thread from some weeks ago) - - but I am having to explore other options.

I've driven Greta for 15 years on points but now don't seem to be able to properly maintain timing ... I of course could be barking up the wrong tree entirely - but she needs to run much more smoothly and efficiently than at present or she'll be sitting RBRR out and watching one of her stablemates do it instead.

Problem is manifest by a gnashing ( I really don't believe it's pinking ) noise when revs reach 4k - carbs are both sucking equal amounts of air, revs are too high for weights in the dizzy to be stuck, too low for valve bounce, rockers set and reset - all suggestions welcome.

 

[glang]

has it got to be an original replacement unit or would one of these new ones be acceptable:

https://www.ebay.co.uk/itm/Triumph-6-Cylinder-Points-Distributor-with-tacho-complete-TR6-GT6-Delco-/121754188486?_trksid=p2349526.m4383.l4275.c10

[richard w]

Have you tried the distributor doctor? I've heard lots of good things about them - and I hope they're right as mine is there at the moment being refurbished! Probably better than a cheap new copy.

[TedTaylor]

Metal cam lobe (or am I thinking the wrong part) worn away by a plastic heal of the points - very unlikely.  I reckon it is something else.

I am with Richard, rather than mess around replacing with second hand items which are themselves likely to be worn (I was lucky in having a low mileage dizzy when I did my swap) get it to the Distributor Doctor - I too have heard good things about him.

MUT

[nang]

Back in my diesel mechanic days, I have seen a nylon fuel line wear a perfect radius in a steel injector pipe. Actually far enough through to leak diesel 

Tony.

[JohnD]

Long ago, I fitted an optical replacement for my contact breaker (Lumenition) and it's never given me a moment's problem, and abolished high speed misses.  It can be fitted to any distributor, so no need to find another with cable driven rev counter.

It never wears out as it's a non-contact sensor, and unlike contacts arcing wear doesn't occur.    Just consider a moment - The Coil and contact breaker sysem was invented by Charles Kettering for Delco in in 1908.    Long, long, long before electronics and transistors, which he would have used if they had.      Transistorised systems have been in use since the 60s.   Since then they have had as long as the Kettering system had to mature, and have become stable, robust and now wholly replace the Kettering system in production cars.  

The only reason not to use a Lumention or similar is originality, or historicity, but that's nota a problem for the OP.

Another issue is the condensor.  They can go bad, which means they conduct and short circuit the points, so ignition fails.   But a condensor is only there to inhibit arcing, which wears the points.  A spare condensor when travelling is redundant, as just removing the bad condensor will restore ignition, at the cost of more rapid points wear.   Like twice as fast, so you'll get home, even from the 10CR!

John

[Hogie]

The point about a soft material (Nylon etc) wearing a harder material (steel).

The soft material can pick up grit type products and these can be very hard.

Roger

[Guppy916]

I used these guys http://h-h-ignitionsolutions.co.uk/#top  01384 261500,

the web site is being worked on so give them a bell,

They did my GT6 it's fantastic no more points or condenser, and the only way you would know is if you take the cap off, 

[English]

I've used the Distributor Doctor (http://www.distributordoctor.com/) for a complete rebuild on a dizzy for a rally TR3a. Martin Jay (for it is he), found the right advance curve to suit the modified camshaft and gave the unit the right amounts of advance at the right time. It's a prerequisite if you take the car to a rolling road.

The result isn't cheap, but deeply lovely.

Andrew

[Greta]

Quoted from English-

I've used the Distributor Doctor (http://www.distributordoctor.com/) for a complete rebuild on a dizzy for a rally TR3a.

Andrew

It's always interesting when a new post appears on an old thread... Since my initial post in early 2018 the GT6 has had no less than four separate engines! Too long a story to go into... but interesting to note that even on the newly rebuilt 4th engine I still had misfiring problems ... I guess I'm still shaking down but after being on points AND Luminition everything is much crisper on the luminition. I've no idea about the advance curves and am still on my ageing Lucas dizzy.
But hey!  very much looking forward to seeing your Rally TR3A perform... Mike & Lorna Harrison used to compete successfully on HRCR events in their TR3 for several years - but not seen them recently.

[Dogsbody47uk]

The TSSC shop now sell distributors. Electronic or points, with or without tacho drive.

[mikeyb]

My Stag has run on Lumenition for longer than the 35+ years that I have owned it.  Despite having a spare module bolted next to the running one for a quick changeover if required, it has only once let me down in over 80k miles of sometimes hard and fast driving. That was due to a broken wire in the optical sensor where it passed through the side of the dizzy (core broken, insulation intact so a bit tricky to fault find initially!).  The same module is still in running service!

Edited August 10, 2021 by mikeyb

[Tim Hunt]

I had a quite early Lumenition optronic system on the 4A with a stamped steel chopper rather than the later injection  moulded plastic one. The power module failed after about thirty years, the system having been perfectly reliable until then, not a bad life. Short term I reverted to points. However, the distributor was worn and I was getting intermittent pinking from worn balance weight springs (remember that the Lumenitioin  still relies on the mechanical advance). I went the 123 fully solid state route 14 years ago, this was a more attractive financial option that a new Lumenition plus distributor rebuild. I carry the old Lucas 25D4 with leads in the boot as belt and braces, it would be a very quick job to swap but I expect never to need it. However it did help out a Dutch entrant in a TR4 on the Border Raiders in 2018. 

Tim

[RobPearce]

The Lumenition on my GT6 must be 25 years old and still good. The only time it gave trouble was when the chap setting it up on a dyno unplugged the pickup and the connector took a bit of fiddling to get back together properly. When I first fitted it, it cured a problem of 20 deg ignition scatter due to play in the shaft making the points gap variable.

When I had a Stag, that disi had play in the vacuum advance plate, which also resulted in variable points gap (on one of the two sets of points) so severe that the engine would die on overrun. Lumenition fixed that problem, too, but I don't know whether it's still running on that unit because I sold the car.

[thescrapman]

8 hours ago, mikeyb said:

My Stag has run on Lumenition for longer than the 35+ years that I have owned it.  Despite having a spare module bolted next to the running one for a quick changeover if required, it has only once let me down in over 80k miles of sometimes hard and fast driving. That was due to a broken wire in the optical sensor where it passed through the side of the dizzy (core broken, insulation intact so a bit tricky to fault find initially!).  The same module is still in running service!

Didn't you knock a bit off the chopper as well once?

I have used Piranha systems on 3 of my cars for many years now.

Edited August 10, 2021 by thescrapman

[mikeyb]

Yes, you are right.  I had forgotten about that.  Can't remember if I clumsily knocked a lug off or something else happened.  I still have said chopper in the boot as a emergency spare, lug araldited back on!  

I have Newtronics / Piranha fitted to just about everything else,  very similar in concept to the Lumenition but not sure if compliant with the historic regs.