[help needed] Nano and Dumb Coils

[detulf]

Hi,

short intro: I'm Detlef from Germany driving a BMW R100 (1000cc, carburator based boxer engine) from 1982 and my plan is to replace the standard ignition system by a DIY ECU to be able to better control the ignition timing and probably add a map sensor later.

So as a newcomer to rusefi, I have a few questions right off the bat regarding NANO's dumb coil support. If I could have found some answers by RTFM, I apologize in advance

About the project: I would like to equip my 1982 BMW R100 motorcycle (boxer/flat twin engine, wasted spark, a dumb inductive coil with two spark plug outputs, carburetor) with a DIY ECU and came across the NANO ECU.
Now my questions: Are there any specifications for the coil in terms of primary resistance, dwell time, etc. so that it works well with the NANO? How much current can the NANO's dumb coil drivers (IGBT) handle? And probably a beginners questions: Do ECU's dumb coil terminals always switch to ground?

And last (for this message) perhaps there is already some experience with a BMW motorcycle and the NANO ECU. I would of course appreciate any feedback.

Many thanks in advance for any feedback.

Detlef

[AndreyB]

Only one thing is known for sure: nano would get damaged if you attempt using it with CDI coils.

[detulf]

First, thanks for your answer. Seems that NANO's dumb coil support is nobody using

In the meanwhile I did some more research. Based on the low primary resistance of my ignition coil (0.7 ohms), the “charging current” can probably be 8+ amps (charging time approx. 4 ms with the standard iginition system).

Do you think that the NANO board, especially the conductor tracks, can withstand these high currents? Or should I consider a different coil or probably deploying an external igniter(?) board (which I normally want to avoid) ? (I mean currents on wiring harness to/from NANO/Coil should be monitored as well, or am I wrong?)

BTW is the IGBT device used on the NANO able to handle those currents?

So many questions ...

Thanks,

Detlef

[AndreyB]

Please confirm that your question is "I have an inductive coil but I want to double-check that you guys have designed the board to properly handle inductive coils"?

if that's the case, the answer would be "We hope that we have properly designed the board to properly handle inductive coils, but only time and user feedback would tell if we have succeeded".

[detulf]

NANO is currently my favourite DIY ECU (dumb coil support, +5V sensor power, MAP sensor support, support for various trigger wheels, TunerStudio as a configuration tool). However, I know that dumb coils are often the critical factor in DIY ECUs and wrong coils are able to quickly destroy the IGBT driver or even the ignition coil, so I am looking for as much information as possible about the NANO ECU. And so YES, I can confirm your assumption regarding my question. It would be great if there were already experiences with NANO and dumb coils here in the Forum...