DIYEFI.org Forum

Has anyone played around with GM DIS dual post coil packs?
(I'm going to post a similar question on MS forum and will share any useful feedback)



I have purchased 4 of these from Jegs to make a wasted spark set-up for a V8. I am curious as to how the OEM's fire these coils, they have two slots for blade type terminals on the underside and normally fit two or three to any ignition module on 4 & 6 cylinder engines. I would like to know if the OEM's alternate the polarity of the coils when they are fired, I don't believe it would make a big difference to the spark other than affecting the sparkplug electrode wear.

If there is no significant gain to alternating the polarity I will just make my own ignitors using IGBT.

I found this interesting site before. It has a good write up on using these coils with megasquirt.
http://www.teglerizer.com/fi/megasquirt ... odule.html

Thanks for the link. Very Useful.
Looks like the OEMs use a simple ignitor set-up that doesn't alternate the spark direction.
I think I'll order some IGBTs and build a small ignitor box near the coils in the engine bay. That will keep the current switching & high voltages away from the ECU.

longracing wrote:I think I'll order some IGBTs and build a small ignitor box near the coils in the engine bay. That will keep the current switching & high voltages away from the ECU.

There are heaps of good OEM parts that you just need to throw on a heat sink. J701 units are found on many mazda and mitsi vehicles and are pretty much indestructible. The part in bold is always a good idea! :-)

J701 ignitors on a heatsink :





Very similar J121 ignitors close up. The difference is only the plug, the older square plug is much less reliable and breaks.

Thanks for the feedback. So far the local wreckers haven't been much help for sourcing small parts like ignitors, connectors or crank-angle sensors.

I ordered some IGBTs which I thought were logic level input but aren't so I'm doing some work on a driver board.
I've attached the schematics in a .pdf but they were created in KICAD if anyone wants them.

I am using IKP10N60T IGBTs from Infineon.

Would appreciate any opinions on the resistor values, schematics, diodes... etc.

i personally am a BIG fan of the Bosch 0 227 100 211 module,
SMall robust and easy to get. best part 4 ignitors in one and you do not need any other components.

Good ground, and your 4 ins and 4 outs.

The Bosch units look great, however I have been chasing them up and found that they are ~AUD$400.00 and $25.00 per connector. And Bosch won't have any in the country until April.

Not too many places nearby carry parts or are that interested in DIY so I think I will do a bit more work on my own ignitor design.

The one change I may make to the design is to use a 5V zener diode between the ignition inputs and ground to protect the ECU outputs.

Can you not get the bosch off some junked euro car??? I would only consider parts that I can commonly and easily get second hand (and of those, only ones that are cheap and reliable).

Fred.

any subaru with an ej20g in it will have this ignitor.

any nissan sr20 with cop with have it.
almost every VAG engine with cop will have it.
Audi, scoda, VW, and more..