M42 Coils....

[Ironhead]

I hope this does not belong in off-topic.....

I wanted to know, do the M42 coils have integral ignitors, or are the ignitors in the ECU?  I am going to implement the M42 coils on a different BMW application with standalone EMS, and I just need to know if I will need external ignitors, or if the M42 coils have built in ignitors.


Thanks!

[bmwman91]

I hope this does not belong in off-topic.....

I wanted to know, do the M42 coils have integral ignitors, or are the ignitors in the ECU?  I am going to implement the M42 coils on a different BMW application with standalone EMS, and I just need to know if I will need external ignitors, or if the M42 coils have built in ignitors.


Thanks!

What exactly do you mean by "ignitors?"  Are you talking about the big cylindrical coil that distributed cars have that fires the spark plugs?  If so, then each of the M42's 4 coils is basically one of those (it would be "internal" as you put it).  You will need an EMS that is capable of driving multiple ignition coils, which most decent ones can, but make sure it can first.

Which EMS are you looking at?

[Ironhead]

Some individual coils have built in "ignitors" that amplify a relatively weak signal from the ECU to a strong enough signal to trigger the coil.  On other applications, the "ignitor" is in the ECU itself.  

I know "some" Motronic ECUs with multiple coil applications have the ignitors built into the ECU.  However, I am using a Motec ECU, and they do not have ignitors built into the ECU (they say because the resultant heat degrades the electronics).

So basically, I need to know if the M42 coils I plan on using can be plugged directly into the ignition outputs from the Motec ECU, or if I need to use an external ignitor between the Motec and the coils.....  This would not be a big deal, I just need to know to facilitate planning the wiring and such.

I am using an S14 which comes with a distributor, so I figured all you you M42 guys would know the answer instantly, at least if you have made mods to the ignition or ECU on your cars....?

[tjts1]

I think you are talking about the power stage.

[Ironhead]

I think you are talking about the power stage.

Uhhhh.....huh?

[bmwman91]

I think you are talking about the power stage.

Yeah, I think so too.  Forgot all about cars that use those....

OK.  So, the Motronic grounds the primary coils via transistors within itself.  There is no secondary "stage" component to run that like a lot of other cars have.  There is no "ignitor" in these coils.  The ECU drives the primary coils, which in turn create the large voltage in the internal secondaries (both of which ar einternal) and make your spark.  The coils are nothing more than transformers.

[Ironhead]

Thanks guys!:)