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Megasquirt Twin spark coils

4747 Views 12 Replies 5 Participants Last post by  Gabor K.
I have a PnP Megasquirt 2 that came of my BMW S38B38 that I want to run on my 75 TS. The MS was setup for coil on plug because the BMW has those. Also, these BMW coils have a build in coil driver.

How would you guys make the ignition work? I know that the BMW is a straight six but you can switch the software to 4 cilinder and not use 2 ignition and 2 injector outputs.

My idea was to use 4 later model twin spark coils and have them fire the 2 sparkplugs of one cilinder.
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Getting the ignition to work should be straight forward enough, but if you want to go multi coil, you're in for some wiring changes.
Have you looked to see if the MS will plug into the older Alfa Motronic plug?
The 75 TS uses external ingition modules so the ignition trigger signal has to go to them.
It's probably a safe bet to say that the BMW engines uses a camshaft driven reset sensor to facilitate full sequential injection (and maybe ignition, but there's not as much advantage there). The 75 TS has no cam speed reset sensor, so you'd be running injectors and any direct ignition system in pairs (1 & 4, 2 & 3) unless you add some sort of cam speed reset.

And while I'm at it, the Alfe engines didn't use linear throttle position sensors, either.
Yes, the BMW uses a camshaft sensor but it is not used with the PnP MS. The throttle sensor is different but I can put the BMW one on it with some fabrication.
But how do I fire all 8 plugs in wasted spark mode?
But how do I fire all 8 plugs in wasted spark mode?
You will only use 2 ignition chanels from th MS. So each ignition chanel will trigger 4 coils.
Obviously you need to use coils with built in ignition modules, or use external ignition modules.
I've got 1 of these QuadSpark Four Channel Ignition Module as part of the (not yet/will it ever be running?) v6, with each chanel driving 2 Yamaha/Denso ignition coils. Tho there is no guarantee that it can actually handle 2 coils per chanel.................. :surprise:

If the TS has 2 separate wires from the ECU to each of the ignition modules, then if those wires line up with ignition chanels from the MS, you should be laughing. But send each signal to, at the very least 2 chanels of a 4 chanel ifnition module. But a safer option is sending each signal to a 4 chanel ignition module.
Maybe ask on the MS forum if there is any reason why 1 ignition chanel can't trigger 4 ignition module inputs like you want.
I was thinking about some later model 156/147 coils and have them fire is wasted spark just like how the setup now is with the 6 BMW coils. They guy where I have the MS from said that I have to switch in Tunderstudio to 4 cilinder. Than 2 coils will not be activated anymore in the BMW harness.
Had je niet beter je s80 kunnen gebruiken,kan je 8 coil-plugs/pen bobines mee aansturen?
Die was van mijn broer en ik ben beter bekend met de software van de Megasquirt. Dat is allemaal wat makkelijker te verstellen.
Ok ik snap het ,bij mij is het precies andersom,alleen bekend met DTA .
Ik zoek een map voor een DTA Twin Spark,heb jij enig idee waar ik deze vandaan kan halen?
Ik heb die van Michel75 gekregen. Die kan ik zo in Tunerstudio laden en anders maak ik hem zelf. Die man waar je de DTA vandaan gehaald hebt helpt mij er bij en heeft een rollenbank. In tunerstudio kun je de 3D map gewoon real life met de muis aanpassen onder het rollen/rijden, echt super makkelijk.
Hoi Jelmer,

Ik heb mijn 75TS motor draaiend op DTA P8Pro ECU. Ik heb 2 coilpack van een Alfa 155 TS (8V) gebruikt. Ik heb op elk coilpack de 2 ingangen gebruikt. Elk coil pack stuurt 4 bougies aan in Wasted Spark.
Dus Coilpack1: Bougie 1 (DIS), Bougie 3, Bougie 5, Bougie 7.
Coilpack2: Bougie 2, Bougie 4, Bougie 6, Bougie 8.

Coil pack 1 en coil pack2 worden door de ECU op het zelfde moment aangestuurd.
De coil amplifiers zijn ingebouwd in de DTA ECU.

Ik heb dat je hier iets aan hebt.




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Ik heb een 3.0V6 24v inmiddels....
In the Twin spark engine with COP, as I see it its one signal to the COP and it gives two sparks. A double COP so to say, governed by one signal. So the ECU should be able to drive this type of twin COP.



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