I need to look at this stuff more in depth. the nano EFI looks cool and I like Steveos idea of making it an all in one type of controller. I also like how precise the opti could be if working correctly and I think it really opens up what you can measure with calculations
The truck coils with finned heatsinks self trigger with too much dwell to stop them overheating it's the built in protection.the delco ecu I use with an external ls1 coil driver box the cranking dwell is too high and if it doesnt crank fast enough and start fast enough they cause a nasty kick back .lots of people with aftermarket ecus have the same issues too
This is how I built my pc oscilloscope https://m.facebook.com/profile.php?i...content_filter
I have always been suspicious of the accuracy of the soundcard oscilloscope. The input is supposed to be 1v p-p, and this one is regulated at 5v, which would allow distortion to crab up the readings, and the arduino based one can display more that two inputs at a time. It's very handy for more than 2 traces, even though it is primitive. Just add more input pins/variables. The limit is how messy the graph turns out.
Last night I put waterproof connectors on my prototype's pigtails and it's ready to go in the car after I seal the case with some silicone. In finishing all this I wanted to test out the extra input I wired for the MAP sensor. I'm happy to report that it looks like manually interfacing to the ADC section of the microcontroller yielded much more reliable and faster results than I had using the arduino analogRead() function with other projects using multiple analog inputs. Unless there's some other unforeseen issue I think this will work very well. And since I retooled the code to eliminate floating point math pretty much everywhere, I built a bash script to convert the raw datastream to human readable values (voltage and rpm, map will follow).
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Getting to this milestone, I have to ask kur4o if he might be able to pick apart the portions of the $ee program pertinent to how MAP effects dwell and explain it in laymen's terms. I'm sure anything I come up with for this will be better than no dwell compensation, but I'd like to utilize this additional input's data in the most efficient way possible.
I'm jonesing for an email from Lloyd telling me my heads are on their way back. In the mean time I'll try to finish the schematic and see what options there are for pcb design. I found this on Monday, but haven't gotten as far as building it or trying it out.
Last edited by spfautsch; 03-15-2018 at 05:38 AM.
So are you adding second map sensor or using the stock one with shared wire. First check for interference between PCM and arduino. Maybe some isolation will be needed.
What I remember it uses some delta map value to find out when the engine was accel and decel mode. The dwell was added only in accel mode. I will dig through it more thoroughly and write back shortly.
The intention was shared wire to the factory map sensor. The ADC inputs on the arduino are fairly high impedance (100M ohm) and using the internal reference voltage will give 0-5v range so no voltage divider will be needed. I don't anticipate a problem doing this, but I will test by disconnecting the map wire from the controller while running and observing if the PCM is reporting a change.
By delta are you saying it stores the most recent map value in a variable and then compares the next reading to the stored one? That sounds simple enough. I'll probably want a deadband around the stored delta value or use some hysteresis logic to prevent oscillation.
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