Rev counter and Electronic Ignition

[Bruce Crowthorne]

Just about to buy some electronic ignition for my S4 and I wonder how they drive the rev counter?

With the points I guess there is enough current through the little loop on the back of the rev counter to drive the meter, but how does it work with electronic ignition?

I am looking at an Aldon Igniter (or possibly a Lumenition set up).

It's probably in the installation manual (but I haven't bought mine yet).

So - how does it work and how do I need to wire it in?

Thanks
Bruce

[Frank Howard]

Bruce,

The tach will have to be converted. The ignition leads going into and out of the tach will have to be connected to each other, bypassing the tach. A new lead will have to run from the converted tach to the negative side of the coil.

[denicholls2]

Frank wrote:

The tach will have to be converted. The ignition leads going into and out of the tach will have to be connected to each other, bypassing the tach. A new lead will have to run from the converted tach to the negative side of the coil.

I would not assume this is the case until you have ignition installed and it does not work. I have Pertronix Ignitor (same as Aldon??) and an RVI tach and it works just fine. I have heard the same from others.

There are combinations that do not work (Lumenition seems to be high on the list of those needing rework) but by no means does switching to electronic ignition mean you always lose your tach.

[Rob_LaMoreaux]

The Aldon/Pertronix Ignitor is a points replacement system and it works, just like points. It has been working great for 5 years now. I have one on my car, as well as an MSD reve limiter. They work fine. Other electronic ignitions that are more than points replacements probably won't work. They need all the current for the coil, and nothing else going through the tach to work properly.

Rob

[Bruce Crowthorne]

Thanks Rob, that is what I was hoping!
I am collecting my head from QED on Tuesday, I'll buy an igniter when I am there.
Bruce

[bcmc33]

I am a little confused ? nothing unusual, of course.
I am close to choosing an H&H Ignition Solutions electronic dissy and coil on the basis of a recommendation and also they are close to where I live.
Following this thread, and others, I asked the question regarding the need to modify the tacho. They said ?no modification necessary?.

So, to satisfy my confusion, which electronic system(s) do/don?t require the tacho to be modified?


Brian Clarke
(1972 Sprint)

[chrishewett]

I have had an aldon ignitor for about two years. Trouble free and the tacho works just fine without any mods.
Chris