The Triumph Dolomite Club - Discussion Forum

Hi All

I am considering converting my 74 Sprint to electronic ignition, with the car currently standard in set up, so points and 6v ballasted coil etc. I have spent some time reading a number of the posts on the board in relation to this topic, of which there are plenty, however it would be nice to have some current views on things particularly when considering an option that I have come across recently that I haven’t managed to find any views upon as yet. Hence the post…!

The Lumenition Magnetronic option seems to be one that has been well documented on the board, and thus is a tried and tested method particularly on the Sprints and it works with the smaller cap. However the more recent one that I have had proposed is the use of a Sparkrite SX4000 (link details below) , which apparently according to the person I spoke to “is ideal for a traditional points and condenser system and works with these parts in place. It amplifies the spark remotely, removing any load from the points themselves. This allows you to keep the traditional system in place but gives you a fully working electronic system, increasing reliability and preventing points burn out. The load on the points is controlled by the SX4000 which acts as the condenser electronically. At the flick of a switch you are able to drop back to traditional points and condenser should that be needed for any reason”.

In using the SX4000 unit, it is recommended that the coil be changed to a 12v version along with the use of differing HT leads, which I am certainly not against if it improves things. So does anyone have any experience of this unit, Dolomite or otherwise that they could share? If not then any views in general on the concept would be appreciated!!

Thanks in advance…!


James R

http://simonbbc.com/sparkrite-sx4000-un ... er-module/

I wouldn't call the Sparkrite system electronic ignition, electronic assisted ignition is far more accurate. Still using your distributor, points and coil so any existing issues in that area are not removed. They do however take the load off the points so that they last longer, clean up the signal from the points and provide a consistent power to the coil. The systems that do away with the points are even better, but clearly the same caveats about components apply, though physical side load is taken off the distributor.

Best option is actual electronic ignition, toothed wheel on the crank pulley, electronics read that, and the manifold vacuum and using a table of values fires the coil at just the right moment. No wear, no need to adjust, always the right spark at the right time. Madmart has written about this and I have all the components to do the same, teh only thing that keeps stopping me is wondering about keeping it all original and because at the moment the ignition has not given me any grief in years.

So the question is how electronic do you want to go?!

I use the britpart module, it is bullet proof, I have never had one go wrong. However it isn't as cheap as it use to be, I think I got my original module for just over tenner and now they are three times that. When you add in the cost of an ambassador cap and new leads, not the bargin it once was. Shame

As for the Sparklite system, it is cheap but the fact you keep the original parts is rather offset by having a dirty great grey box mounted in the car. Plus I have my doubts about their claims. Sure the points won't be eroded by the spark but it still a physical switch opening and closing, so it must wear eventually.

True electronic systems use a contactless trigger like a hall sensor or an optical sensor.

With the Sparkrite system, the electrical load on the points and condenser is theoretically removed, but the mechanical load is there still so the cam heel will wear leading to constantly changing dwell and timing and you are still gonna have to mess with it regularly to keep it in top form. Also any wear in the distributor shaft bearings will still lead to sub optimal running.

A proper electronic system solves all these issues and there are several ways to go.

123 programmable distributor, cost a small fortune but gives best results and is bulletproof.

Lumenition Optronic, still subject to vagaries of mechanical distributor advance curve, but the best of the aftermarket kits, circa £200

Lumenition Magnetronic, same advance curve limitations, but cheaper at circa £70. I personally have removed several failed ones so am not a fan.

Britpart/Accuspark cheapies, around £30 but you need to fit a different cap(Ambassador) and rotor to make it work in a Sprint at all, others have reported these as unreliable, my own experience with them is more positive, i've never had a failure on one i've fitted, but i've never put one on a Sprint! Also the quality of available aftermarket Ambassador caps is not very good!

Or you can go "distributorless" with a standalone ecu and Megajolt with a crank sensor and coil pack or even (for advanced techs only) build your own with a Ford EDIS. If you are electronically savvy and good with your hands you can build a DIY one for very little money using a salvaged EDIS unit, Proprietary ones like Megajolt, prices vary wildly but are increasing steadily. Note, you can't actually delete the Sprint distributor when doing this as it forms a link in the oil pump drive between the jackshaft and the oil pump!

Steve

Which ever you choose , keep a dizzy built up in the boot in case you need to drop it in one day in case you do have a failure of the electronic type. Ive been using the Britpart module type for a few years with good results after the first one never worked at all. (they replaced it). I'm now EFI so not so much an issue (yet!)

Tony

Carledo wrote: ↑Fri Sep 27, 2019 10:24 am

Britpart/Accuspark cheapies, around £30 but you need to fit a different cap(Ambassador) and rotor to make it work in a Sprint at all, others have reported these as unreliable, my own experience with them is more positive, i've never had a failure on one i've fitted, but i've never put one on a Sprint! Also the quality of available aftermarket Ambassador caps is not very good!


Steve

The only time I had a britpart module not work was because the magnetic trigger was not quite seated right on the dizzy shaft.

Haven't had any problems with using it on a Sprint, apart from a dodgy rotor arm. Handily Lucus dizzys are all made to a similar design. My guess is they changed the bob weights/vacuum unit to get the right advance curve for a particular model and left the rest pretty much the same. So there is no reason why it shouldn't work.

I agree that having a fully programmable system would be nice but I can't justify the cost.

Thanks for all the responses, which are very informative and helpful...

Only problem i have is that electric isn't my strong suit so going to be challenging to consider everything that has been said and plan a way forward that i will be able to undertake without too may hitches. For the immediate short term does anyone have any views on the best place to get a quality set of points or are they all suffering from low demand thus poor build quality?

Thanks again all!

Hi James, If your points have been in there for some time they will probably be genuine Lucas ones and will respond very nicely to being removed and cleaning the contact faces with a fine file and then polishing with some very fine emery paper.
Keep the contact faces parallel as far as possible; and remove just enough of the hard metal to get rid of pitting. Set 10 deg BTDC on the timing marks so its easier to verify the timing afterwards.
PM later.
Tony.

I would not recommend the magnetronic system I have had two fail and got so fed up with it that I went back to points.

You can get the Britpart kit HERE It is a direct replacement for the points and condenser for the Lucas dizzy. For the Sprint, you will need the 45D4 rotor arm and Ambassador dizzy cap. The 1850 can use the 45D4 rotor arm and cap but needs the adaptor plate so that the ignition fires at the right time. I had this setup in my 1850 for quite a few years.

Hi Dave, How do you get the Lucas cap to work with the A.C. Delco 1850 dizzy ? I have samples of both here and the shaft is too long to fit under the cap .
Tony.