SafeGuard Inductive Multi Spark

[@jselectronics8215]

Software adjusts dwell to maintain 8 amps peak coil current.

[@esaikonen6546]

Interestingly, hopefully we'll see it ready for sale.

[@jselectronics8215]

I made the video about a year ago. I had a lot of videos up but I accidentally deleted the channel. Everything is done in software, so I could add the feature at any time, but I don't see a real benefit, other than as a marketing gimmick. It looks cool, and was a challenge to program. "Hard Fun", to borrow a phrase from electronic cookbook author Don Lancaster. I did it because there was a question on the speedtalk.com forum about the Pertronix Multispark. I asked if anyone had seen a video of the waveform. No replies, so I imagined what it might look like and spent a few weeks on it. The first spark has variable dwell with RPM, just like the standard unit. That's good, but the spark is cut off after 200usec. That's bad. But that's what you have to do if you want multi sparks. The dwell time for the rest of the sparks is set to 250usec, with a 200usec burn time. That's bad. We want a longer dwell time, and a longer burn time. The only way to do that would be to limit the number of mini sparks, and even then, it would be less than if just making a single, long duration spark. All the while you are making crappy sparks, you are stressing the ignition transistor. Of course, you could get a bigger heat sink and better transistor, but the sparks would still be crappy. And look at the flyback voltage. On my standard version, the flyback voltage is over 400v. Here, you can see it decrease with the number of sparks. Thanks for watching. I'm sure I've seen your name somewhere...?

[@shortedtoground]

@@jselectronics8215 In some of the Ford classes I used to teach, we went over their repetitive mode which was another name for multi spark. From the factory, vehicles had it to run leaner mixtures at Idle while preventing misfires with the extra sparks. It would shut off around 1,200 RPM's. I used to look at some patterns on a lab scope and saw three sparks until raising the rpm's shut it off. This is cool stuff, thanks for posting this video!

[@davidmaye3580]

Interesting!!!! A little hard understanding exactly what's going on here but sure is noisy.