Help with building your Speeduino, installing it, getting it to run etc.
Coil upgrade/replacement - not overthinking. Issue - coil resistance, accepted industry standard is approximately for a 3 ohm coil. Coil circuit has an amp reading of approximately 3.5 amps. Using a coil with an ohm reading of approximately 1.5 amps doubles the circuit current to say 7/8 amps.

Thinking about this because the Speeduino design and build is all about current (amps). Other electronic components should be no different - coil drivers.

Read a lot of forum threads where the OP has used a specific coil pack and coil driver and these have failed after a short time. Looked into this, and found that coils that spec out at approximately 3 ohm have an internal resistor, those that spec out at a lower resistance generally have an external ballast resistor of sorts or use a resistance wire that raises the circuit resistance to approximately 3 ohm. The 3 ohm coil circuit has amps of approximately 3.5 or so. Reducing this to say a 1.5 ohm coil, circuit amps double.

Too little current in the system and there's not enough oomph to get and keep the engine going, too much current and components start to fail, coils overheat and fail.

Having mentioned that I am upgrading the coils, don't want to "fry" new components so will be testing the new coil pack(s) and possibly including an additional circuit resistor if necessary.

Time to peruse the forum to look for info regarding this.
You can see @apollard has a handle on what it's supposed to do, and how to get there.

More learning concepts, and less thinking without sufficient basics. If I had one suggestion, it would be to clear your mind of all those many assumptions, and study the basic concepts, so you can accurately understand what's going on or the goals. You know a little, and so you try to fill-in the gaps on your own with whatever makes sense to you, rather than relating it to established principles. That's what I think, and I could be entirely wrong. ;)

For sure, do not use industry standards without also knowing the control mechanism and principles. 3-ohms was industry standard 50 years ago. What changed? What "sounds good" is not what "is good". If you know basic concepts and principles, you can answer why conversions may use GM HEI modules instead of Honda drivers, or 3-ohm vs 1-ohm. The web is dangerous as some is good, but much is limited or false, and you can't tell which without the basics to guide you. Use technical references as a foundation, and correlate what you read to that.

Without those basics, you are guessing and then assuming, and it's often wasting time and brain cells on the wrong path to the wrong conclusion. Start reading about Kettering, induction, spark ignition, dwell time vs amps and saturation. Then relate that info of what the job is, and how it works, to how you can get the job done. Best of all, you'll then know why you should do or not do stuff. I'll respond to your big post with my perspective when I get back from a meeting. Rock on!
Rednaxs60 wrote: Wed Mar 15, 2023 3:49 pm Coil upgrade/replacement - not overthinking. Issue - coil resistance, accepted industry standard is approximately for a 3 ohm coil. Coil circuit has an amp reading of approximately 3.5 amps. Using a coil with an ohm reading of approximately 1.5 amps doubles the circuit current to say 7/8 amps.
The energy in a coil is the square of the current multiplied by the inductance. Modern coils have a low resistance which allows higher currents and more energy. Electronic control of the dwell time means they are energized for the minimum period necessary minimizing heat, spark plug gaps are generally 38 or 40thou.
3 Ohm coils were the norm back when contact breakers were used, dwell times were huge at low RPM and and if the ignition was on with the engine not running the coil had to be able to withstand the coil being on permanently, spark plug gaps were usually around 25thou.
Ballast resistors were brought in to allow the use of lower resistances to improve the spark during starting when the battery voltage was lower, they don't offer any other advantage
With electronic control lower resistance coils were able to be used and these give higher energy in a smaller package.
3 Ohm coils will work with Speeduino, so will lower impedance coils, you just need to set the dwell times appropriately, lower impedance coils will give a better spark.
Thanks to all for the info on coils. Going with the J723T coil driver and Opal Cross coil pack primarily because of plug wire orientation and wire connections on the J723T coil driver. Connecting the J723T coil driver seems straight forward.

OC1 and OC2 from the coils
IB1 and IB2 from the ECU
GND for ground

Do not need VB or Tacho connection

Going to look at the throttle plates for TPS adjustment. Have two sets of throttle plates, right and left cylinder banks. There is a small adjustment screw on the right side throttle connection specifically used to balance the right/left cylinder banks. Not an exacting calibration setup, but good enough. Will be taking numbers 3 and 4 injector holders off to check throttle plates. Doing this because this is quickly becoming a "unique" install, and I've been reminded that this is not a Honda setup 8-)

Will be using a vacuum reservoir for the vacuum system. Have read in various threads that this helps with the MAP sensor reading. I'll find a good spot for it:
Vacuum Resevoir.JPG
Vacuum Resevoir.JPG (62.16 KiB) Viewed 1321 times
Rednaxs60 wrote: Wed Mar 15, 2023 1:35 am Heading into Phase two of the project. Going back to basics and start fresh.
As you are stepping to a new phase and summarizing your reasoning, I will do the same, on the same points. I think you should keep this thread active for theorizing, and probably start a clean new thread with the conclusions, assembly, testing and tuning. If you show how you installed an ignition driver, and changed from the Honda to a different one, you can reference this thread for all the reasons why if readers are interested.

Perhaps Phase 2 or something "new day". This would likely follow actual project success, only encapsulating final actions and results, not the extended deliberations as in this thread. To clarify some stuff, the previous pages won't help others as much as direction from your new... direction :LOL: How you got to here is far less important than where it will go from here. Many of your "upgrades" are just changes you picked, not knowing why. For examples using inline quotes from your post, context from my observations:
  • "Wheel decoder system" - the OEM wheel could work well. It was the OEM proprietary cam wheel that was weird, and you solved that once you got far enough to recognize it.
  • "Making an older OEM FI system and components work with a new aftermarket ECU is not as easy as I thought." - Often true, but much easier than you have made it so far. You would do better to have started with the bike minus the OE ECM. Then no double-tracking for old ECM understanding or confusion would appear, and focus on what the new ECM needed (and not) would be clear.
  • "OEM FI components for more modern, and tested FI components may/will assist in bringing the project to fruition faster." - Sometimes, but reality is that everything on your bike is usable for conversion, except the ECM and cam wheel. Capture all original hardware, change the cam wheel and wire-up the ECM with injector resistors, start and tune. Did I miss anything?
  • "Coils - the OEM GW coils are good for the OEM purpose built system. These coils have been found to be acceptable, but are not equivalent to the more modern coils." - They work, and could work here at least as well as before. Newer might be better, but not required. That is an additional personal choice to making an EFI conversion.
  • "The spark igniters are specific to the OEM CFI system." - Yes, but they can work. Using different drivers is your choice, not your requirement. Did you intend a simpler conversion, or a new custom system?
  • "Most GW EFI conversions use more modern coil drivers such as the GM 7 pin HEI coil drivers even when OEM coil drivers are available." - You do realize HEI module designs are just as old or older than your bike, right? ;) HEI drivers were chosen for their current-limiting (not needed with Speeduino), not that they are better. Right stuff, wrong reasons, unrelated to Speeduino.
  • "You can use the OEM injectors - low impedance with a resistor pack, or upgrade to high impedance injectors." - Indeed, they are optional, and are often no upgrade, as the spray pattern is often less suitable than the originals. The originals will run just fine, as they have been.
  • "OEM CFI system design is an issue that must be rationalized." - I beg to differ. Examining the OE ECM only distracts from focusing on the new control. It also adds unnecessary confusion. The goal is to take your hardware and control it with Speeduino. Focus on that and what Speeduino needs to do it. How the OE ECM did it is effectively irrelevant and a huge resource sucker.
Your quote of me near the end is out-of-context, and was when you didn't have any idea what to do or with what, and we couldn't see or test your parts to know how to help you. You were lost, and my comments offered a possible option using known components, ignoring the old and focusing on Speeduino. With accumulated hardware (not ECM) info, we now know that only the cam wheel requires modification to work with Speeduino. Much of your research has been by web opinion, rather than based in sound principles.

The point of all this clarification is to remind you and others coming this way, that much of the struggles and frustration in these pages are unnecessary in a Speeduino project. We have all tried hard to help you help yourself. Study what is necessary and what is not, or optional, by focusing on Speeduino. With all that off the table, I do look forward to focus and progress. 8-) This one is OK for documentation sake, but too full of distractions, assumptions, side-tracks and frustrating deviations to be of high value to others. Let them make their own mistakes and give them the meat they can use today, to get it done today. :D
There have been 1100 posts over the 2 topics relating to you Goldwing, and you have not been able to get it to even idle properly yet!

You don't know what you are doing, and you won't follow instructions when people try to help you. Sometimes you agree that something is a good idea, but then go off and do something else! Other times, peeople offer ideas, and you don't give feedback.

An example is the coils. you say when you pull the lead on one of the spark plugs, it doesn't make much difference to the idle. So you think about buying coils. I say, swap the coils, then leads, then plugs. Determine if the fault follows. You basicly came back and said you had spare coils. That isn't feedback, and isn't a diagnostic test for the coils. swaping the ones on the bike is, to see if the fault follows is.

It's difficult to help you, because you don't help yourself.

Get on with it :)


My remarks are intended to be constructive, rather than caustic. However, no one is forcing me to read your topic, so do as you wish. :)
My concern is the difference in vacuum between the two banks, has that been resolved yet? trying to tune an engine that isn't running at its best is going to tricky. the OEM ECU may be able to compensate but it has an optimum tune and is likely to be much more sophisticated in its firmware.
I don't recall or missed the bank vacuum differential thing. Is the engine hurt or something? I wouldn't worry about '85 Honda being too sophisticated based on when we used other Honda pre-OBD stuff. ;) It's amazing how crappy simple but proprietary some OE stuff was back then. :lol:
PSIG wrote: Fri Mar 17, 2023 10:41 pm I don't recall or missed the bank vacuum differential thing. Is the engine hurt or something? I wouldn't worry about '85 Honda being too sophisticated based on when we used other Honda pre-OBD stuff. ;) It's amazing how crappy simple but proprietary some OE stuff was back then. :lol:
You'll have to search back for the pics:
A couple of other issues I have had over the years and never to be resolved is balancing the two cylinder banks, cannot balance the cylinder on one side. I have never had better than 9" of HG (in the red zone) regardless of what I did:
Cylinder Bank Balance.jpg
Cylinder Bank Balance.jpg (84.9 KiB) Viewed 574 times
The vacuum gauge indicates that when the reading is in the red zone, it is "late valve timing, or leak at intake manifold or next riser". More than 15" of vacuum and it indicates late timing. Vacuum should be in the 10" to 14" of HG range.
I only have experience of Densos back to around 1987 but they have better resolution, separate idle tables, more corrections and they are coded much more efficiently so there probably isn't a speed advantage either. I'm not saying that they are too sophisticated just not as crude as a Speeduino.
  • 1
  • 57
  • 58
  • 59
  • 60
  • 61
  • 72
Running a k24a2 w/o a chassis

Good point! I guess for starters, is there a trigg[…]

Have you tried Missing Tooth (crank) as a 2-1 wh[…]

BMW E23 M30B28

The issue got worse recently. From the logs I can […]

Cool. 8-) Yes, it's actually simple to do basic[…]

Still can't find what you're looking for?