jakestew

Thanks for pointing that out, but I do understand that CDI has no dwell time.

I just didn't know what else to call the length of time that the processor drives the spark output trigger pin low. I probably should have called it "trigger pulse length" or something similar. But if you did want to use the same program to run a TCI ignition it actually would be correct.

Does a TCI ignition deliver multiple sparks during the dwell time?


On another note... I was trying to see how fast the CDI could spark. I was only able to get my unit to throw sparks every 4 ms.

That means you could only throw a spark every 15 degrees at 1200 RPM. So there probably isn't much use in throwing more than 2 sparks total, and even then only at low RPMs.

Of course, my tests might not mean much. I was throwing hundreds of sparks to see at what speed the unit would quit sparking. My ignition coil also has a little gap in it and I was just using wire ends instead of a stable and normal spark plug gap. The gap did seem to affect the speed the sparks could be thrown.

This test also might not apply to only throwing a few sparks every so often. I only used this test method because it's really not possible to see seperate sparks at such fast speeds. Hopefully I can figure out a better test method or use my scope on the output directly. I'm a little worried about attaching my scope directly to such high voltage though. And I think an inductive timing light would probably just pick up the attempted spark even if it didn't actually spark at the plug.

If anyone has any ideas on this please help me out.


-Jake