Electronic versis points

[William2]

Although I have fitted electronic ignition to my car it did occur to me that if it ever failed then the engine would just die on you. I guess there still is a benefit over fitting the old contact points for reliability. There has always been the argument over accessibility but I suspect that most Elans these days don't cover many miles annually.

[rgh0]

The real benefit of a good quality electronic system is that it is reliable with no maintenance. You can get the same reliability from a points system you just need to regularly service it. The downside of an electronic system is when it dies it often does it totally and unpredictably and you cant fix it beside the road to easily.

My S1 Esprit and Plus 2 have both been on a Lumenition optical electronic ignition system since the early 80's with no problems ever. But i have also carried in the glove box of both cars the points and condenser to reinstall if it ever lets me down. My Elan runs points still as it is a requirement for my racing class and for a competition car pulling the dizzy a couple of times a year to check and clean the points and replace if needed is no big hassle.

cheers
Rohan

[RotoFlexible]

This will probably become a discussion along the lines of oil or grease for trunnions, but for me:

Give me that old-time ignition
Give me points and condenser
Give me that old-time ignition
It's good enough for me!

It was good enough for Colin
(It was cheap enough for Colin)
It was good enough for Colin
It's good enough for me!

It was good enough for William*
It was good enough for William
It was good enough for William
It's good enough for me!

(repeat first verse)
(For our non-American readers, the original song is "Give Me That Old-Time Religion")

* "William" is my engine builder, who has extensive experience building racing English Ford-based engines. He was fine with points and a Bosch "blue" coil. What Bill says, goes. I have had bad luck with a variety of electronic systems, and I'm happy to have something simple that I can diagnose and fix.

[Craven]

Hi,
There is a halfway house that was used in the early days of electronic ignition systems.
Points are retained to provide the switching of an external box that had the capability to switch the high coil current.
Advantage being the points now only carries a small trigger current and do not need to handle the high voltage produced by the back e.m.f from the coil, one cause of contact errosion.
Very small modification needed with this system and can be arranged so a quick easy return to the original points, if the electronic box fails.
But with the improvements in technology this idea is now pretty much redundant, today there are literally millions of vehicles that use purely electronic ignition systems, including separate coil for each cylinder for instance.
In my opinion the Capacitor discharge system is the way to go, but if you are electronic technology nervous then this is probably just a step too far.
Ron.

[tvacc]

Petronix has left me standed 3 times....give me "old time religion" any day of the week...

Tony V

[john.p.clegg]

Ron
Is this it?...

http://www.ebay.co.uk/itm/Classic-Mini- ... Swr7ZW3a4A

John

[Craven]

Hi,
The fact I can see no reference to the special high voltage coil required in a Capacitor Discharge System would make me think No
http://www.mgb-stuff.org.uk/sparkritesx2000.htm
Basic operation, an electronic inverter generates some 400 volts which is then discharged through a high voltage coil.
http://www.burtonpower.com/msd-6a-elect ... -6201.html

Ps. I think the Lumenition power unit can be triggered by the standard points if you really want to keep them in place for a roadside repair by a simple bypass connection.
Ron.

[vxah]

If I recall from years ago the CD ignition systems you could buy were no good for the (then) modern engines that run quite lean at cruise conditions? The very quick voltage rise was good for firing fouled up spark plugs as there was not time for energy to leak away through the carbon etc however, the lean mixture needed a long spark duration in order to get the fuel ignited and a CD system would often cause misfiring at cruise because it had a very short duration.

In my mind an aftermarket ignition system really needs to eliminate the cb points to counter any distributor bush wear that can cause changes in spark timing between cylinders. I think the Lucas type used in the twink are pretty robust but have you ever looked at the AC Delco units fitted to the Viva etc? I seem to recall on occasion you had to open up the points gap just to get one cylinder the fire!

My understanding of old type cb ignition systems is that they are a bit compromised in that to get a powerful spark at high rpm you need a large dwell angle but if you do that the coil will overheat at low rpm's? A good quality aftermarket system can have variable dwell for best of both worlds? Not to mention a mapped advance curve to do away with those worn out bob weight pivots and tired springs...

I'll get my coat....

[Quart Meg Miles]

...My understanding of old type cb ignition systems is that they are a bit compromised in that to get a powerful spark at high rpm you need a large dwell angle but if you do that the coil will overheat at low rpm's? A good quality aftermarket system can have variable dwell for best of both worlds? Not to mention a mapped advance curve to do away with those worn out bob weight pivots and tired springs...

I'll get my coat....

The later cars with ballast resistors overcome the speed problem to some extent as the natural ring of the coil is faster due to its lower inductance.

A problem with the Ford engine, especially in Lotus form, is the distributor right-angle drive which is sensitive to end float in both (dummy) cam and distributor shafts as well as backlash in the gears. The long chain of the Lotus doesn't help and at idling speeds the ignition timing often hiccups audibly. I remember the chief mechanic of the Anglesey dealer unsuccessfully trying to tune out the hiccup in a customer's car by tweaking the Webers back in 1966.

[Craven]

In order to overcome the inherent sort duration spark of a CD system designers incorporate into the idle and low rpm operation, Multi Spark Discharge, speaks of itself really in the single spark becomes a series of sparks effectively a long spark.
The trigger from conventional points is as normal a 0v to 12v transition, that causes a charged capacitor ( 400volts or so ) to be discharge via the coils primary, this is the only time current is flowing in the coil so it remains cool, dwell time as such plays no direct part in coils current.
Ron.