rusefi sequential 6 cylinder ignition multispark vs single spark

Hardware inside and outside of the ECU
Post Reply
gurov
Posts: 37
Joined: Wed Feb 07, 2024 10:43 pm
Location: nj
Github Username: ggurov
Slack: ggurov
Contact:

rusefi sequential 6 cylinder ignition multispark vs single spark

Post by gurov »

nobody asked for this, but here's a comparison of spark sounds, running somewhere around 1000 rpm maybe, settings of max 3 spark, 2ms additional dwell. main dwell at probably around 4ms. these are GM coils with built-in igniters.

multispark: https://www.youtube.com/shorts/l0-3FadAFIo




single spark: https://www.youtube.com/shorts/euJszofUT78


multispark sounds cooler.
1994 6speed supra turbo [ single turbo/1000cc ID/twin fuel pumps/bc2 262 cams ]. J&S safeguard for knock , UAEFI / 407 disco with rusefi / AEM EMS v2 / MS3pro PNP / Speeduino (mega2560 / teensy41 / stm32f411)
2020 BMW X3m - bootmod3 stage1
gurov
Posts: 37
Joined: Wed Feb 07, 2024 10:43 pm
Location: nj
Github Username: ggurov
Slack: ggurov
Contact:

Re: rusefi sequential 6 cylinder ignition multispark vs single spark

Post by gurov »

couple more that nobody asked for, but as i'm testing things for melting, i took a video:

250-ish rpm, cranking mode, 6 cylinder sequential ignition, and injection, but injection is simultaneous while cranking:

https://www.youtube.com/shorts/v0IeTYYb0yA


and 700-ish rpm running mode, sequential ignition and sequential injection, no longer simultaneous:

https://www.youtube.com/shorts/hcnJLM9AdGU
1994 6speed supra turbo [ single turbo/1000cc ID/twin fuel pumps/bc2 262 cams ]. J&S safeguard for knock , UAEFI / 407 disco with rusefi / AEM EMS v2 / MS3pro PNP / Speeduino (mega2560 / teensy41 / stm32f411)
2020 BMW X3m - bootmod3 stage1
gurov
Posts: 37
Joined: Wed Feb 07, 2024 10:43 pm
Location: nj
Github Username: ggurov
Slack: ggurov
Contact:

Re: rusefi sequential 6 cylinder ignition multispark vs single spark

Post by gurov »

this is what multispark looks like on logic analyzer:

1 5 3 6 2 4 firing order


D1 = 36-2 wheel
D2 - D7 = cyl1-6 ign

maximum 3 extra spark
this is about 1000 rpm, main dwell is 4.2ms

(right click -> open image in new tab, to actually see wtf)
image.png
image.png (20.44 KiB) Viewed 6114 times
1994 6speed supra turbo [ single turbo/1000cc ID/twin fuel pumps/bc2 262 cams ]. J&S safeguard for knock , UAEFI / 407 disco with rusefi / AEM EMS v2 / MS3pro PNP / Speeduino (mega2560 / teensy41 / stm32f411)
2020 BMW X3m - bootmod3 stage1
mck1117
running engine in first post
running engine in first post
Posts: 1496
Joined: Mon Jan 30, 2017 2:05 am
Location: Seattle-ish

Re: rusefi sequential 6 cylinder ignition multispark vs single spark

Post by mck1117 »

See also my original video of coil primary current when I implemented it:
JohnP
Posts: 3
Joined: Mon Apr 11, 2022 7:23 pm
Location: SoCal

Re: rusefi sequential 6 cylinder ignition multispark vs single spark

Post by JohnP »

Cool. In 2018 I modified the code on my Universal knock controller to do multispark.

I know the ignition on the modular Fords makes three sparks below 1500 RPM but I didn't investigate use for starting and idle. I was just seeing if I could do it.

There was a thread on the speedtalk forum about an inductive ignition with multispark from Pertronix, but no one had a photo of the waveform, so I decided to try my own version. I deleted the video in the link, but posted an updated version.

https://www.speed-talk.com/forum/viewtopic.php?p=723611#p723611

I could set the initial number of sparks, the dwell, and the "coil off" time. In this video, it's five sparks, with 250usec dwell and 200usec coil off time. It was all done in software, no mods to the hardware, so it's zero dollars, but I decided not to use it. Maybe I should look at it again?

Thinking is hard work
Post Reply