Help with building your Speeduino, installing it, getting it to run etc.
#66870
Back on the road. Still a few things to clean up, but progressing well. Ride with the computer on the shelter, dials are very telling. Operate in the 2800 to 3000 RPM range for most part, this is the start of the power band. Notice that the lambda/AFR gauges indicate that the engine tune is rich. Will be adjusting the VE table to compensate, a little at a time. Going to look at the plugs tomorrow and determine if a fuel injector swap is needed. Have read up on this and swapping injectors to determine the best fit will be done before I get to ICFT. Attached is the engine tune and data log from today's ride. Got in some 70 Kms or so.
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Progressing with KiCad as well. Best way to learn is to use, make mistakes, correct and go forward. Modifying symbols from the various libraries to suit, and have started using extra sheets subordinate to the main schematic.
#66887
Weather is not cooperating. Have the bike on the lift for some additional maintenance issues I want to address. Have been reviewing the data log from yesterday's ride, some 80 Kms or so. Looking at the MAP readings at the various load and RPMs. I mention that I ride in the 2800 to 3000 RPM range, this is a minimum. I notice in the data log that when riding in a static RPM range, OD and 3000 RPM, values stabilized for the most part. Every now and then the fuel injector PW would have a blip so to speak. Also noticed that the Lamda/AFR readings would stabilize in the 0.7/11 range, rich condition. Compared the ECU VE Table values in the load/RPM range that I was trying to maintain. I had already identified the main area that I intend to adjust, load in between 60/90 Kpa, and RPM range of 2000/4000 RPM. Did a VE table comparison in MLV and noticed that the comparison was similar but with new values that indicated leaner VE table cell values were required. Some of the changes were more radical then I would do at this time. VE Table differences:
VE Tables 26 Jan 2024.jpg
VE Tables 26 Jan 2024.jpg (292.56 KiB) Viewed 2683 times
VE Table values below 2000 RPM are not of concern at this time as most road riding is above 2000 RPM. I have colour coded the area I want to address so I can do small area changes at a time. Yellow area first, Cyan directly above the yellow area, green area then the other two.


Checked the spark plugs for colour. The plugs are not that bad. Picture:
Plugs 26 Jan 2024.JPG
Plugs 26 Jan 2024.JPG (84.55 KiB) Viewed 2683 times
Number 4 cylinder plug indicates the leanest burn, will be swapping out the fuel injector to see if there is a difference. The fuel injectors that are in were serviced last year, the ones I will use for a swap serviced in the last two years. Number 2 cylinder indicates the richest colour so it will be used as the base.

The engine operates quite well, but since there is no acceleration enrichment, the engine takes a hit sometimes when accelerating. There is no overshoot when the engine comes to an idle, settles in nicely at approximately 1100 RPM, could go a bit lower.

Next road trial I shall adjust the ECU VE Table values so the Lamda/AFR gauge indicates a leaner burn. Small changes only.
#66909
PSIG wrote: Sun Jan 28, 2024 5:14 pm What data are you using to determine best fueling at (example) 2000 rpm and 70 kPa? How do you know you have found best fueling?
I'm using the data log I posted in post #66870. Won't know whether I have found the best fuelling until I start adjusting the VE table cell values. For instance at time 3613.472s, there is a change for what appears to be no apparent reason. I notice that the AFR was at steady state of approximately 10 AFR then went up and back down. Will know more with some incremental changes to the VE table cell values.
#66911
Rednaxs60 wrote: Sun Jan 28, 2024 10:06 pm
PSIG wrote: Sun Jan 28, 2024 5:14 pm What data are you using to determine best fueling at (example) 2000 rpm and 70 kPa? How do you know you have found best fueling?
I'm using the data log I posted in post #66870. Won't know whether I have found the best fuelling until I start adjusting the VE table cell values.
Yes, but then when you adjust, how will you know when you hit the best fueling?

Rednaxs60 wrote: Sun Jan 28, 2024 10:06 pm For instance at time 3613.472s, there is a change for what appears to be no apparent reason. I notice that the AFR was at steady state of approximately 10 AFR then went up and back down.
You may need to reconfigure your MLV traces, as the reason for the lean bump (if you can see more data relationships) has multiple indicators for cause.

Here I have a section of your log in that area, and you can see the red-line AFR go leaner as you said. Note the green-line TPS reduces from 17.5 to 10, so you're reducing throttle and your MAP falls from 88 to 77, into a new VE cell that drops from 71 to 49 with almost no yellow-line RPM change. AFR has no choice but to follow.

Doing that, notice the yellow line PW that falls-off from 4.918 to 3.237 (as does DC), so the multiple effects together indicates that reducing throttle (and everything that changed with it) caused a leaning of fuel, how it is currently tuned. Use the little gauges and select lots of traces so when one thing changes, you can see anything else that changes. Relationships. 8-)

AFR+ from TPS-.jpg
AFR+ from TPS-.jpg (115.52 KiB) Viewed 2575 times
#66913
@PSIG - thanks for taking the time to review the data log. Have reviewed your comments and the picture and agree with your premise. How will I know when I hit the best fuelling, good question. "TPS reduces from 17.5 to 10, so you're reducing throttle and your MAP falls from 88 to 77, into a new VE cell that drops from 71 to 49 with almost no yellow-line RPM change", looking at the numbers you have mentioned, would seem to me that a more linear/smoother change would be what I should be looking for. AFR is following well and as expected . I think the best fuelling tune should be looking for minimum MAP, as with idle tuning and as you have mentioned on several occasions. Other indicators that are a result of the engine tune is engine temperature (less fuel into the cylinders - hotter engine, had this happen before I started this project), plug colour, engine timing and others. Like you mention "relationships". Small change(s), ride, analyze (learning about this).
#66982
Quick update. Progressing the engine tune in the garage at idle, weather is supposed to cooperate, will be on the road tomorrow. Adjusted the engine tune at idle, idle timing is at 15 degrees instead of 17 degrees. Have to look at the WUE, change in timing has affected the warm up, but once at idle quite good. Blipping the throttle and the engine settles back into idle quite nicely.

Had the engine at idle in the garage and turned the O2 sensor on, both simple and PID. The AFR/lamda readings diid not fluctuate, good sign I have read. Road trial will still be done with the O2 sensor "OFF".

Want to adjust the load levels in the three tables so these are the same, but TS is not being cooperative - keeps reverting to what I changed. Want each table to use the same values. Will work on this.

On the KiCad front, have made a footprint for the DC37 connector - a bit more editing to do, size of the through holes and such. Good learning experience. Using KiCad 7 and there are differences between it and older versions. Have to find out how to do the "net" values to sync up the various components and the footprints.

Cheers
#67052
Update on road trials. Have a route of some 80 Kms, lots of variety in speed and terrain. Adjusting the VE table in the 2000 to 4000 RPM range at the moment. Don’t ride in the 1000 to 2000 RPM range, pass through this quite quickly. As I have mentioned, engine settles into an idle quite nicely.

3000 RPM in 5th (OD) is approximately 100 KPH. 4000 RPM in 4th is approximately 100 KPH. 3000 RPM in 3rd is approximately 60 KPH.

Notice that the fuel consumption is more than I am used to so will be keeping watch on this. The bike has a 21-litre tank and I should get 350 to 400 Kms from a tank cruising on the highway, solo or two up.

Noticed that the ignition timing at 3800/3900 RPM is at 40 degrees BTDC and the spark table is set at 38 degrees BTDC. The IAT temp was at 10 degrees C, expecting this is part of the explanation.

Have adjusted the VE table cell values to lean out the air-fuel mixture for the next ride. Thinking a tweak of the ignition timing may be in order as well, but not until after this next ride.

Latest tune and data log attached.
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#67057
Cool. It drives. 8-) I see your cruise AFRs are so rich the numbers are pegged at the 10 AFR rich limit. Your economy should be about like a school bus. :lol: Idle and power (well, any) best AFRs are not yet known, and likewise you have to find the economy cruise AFRs and timing. While 15.5 to 16.5:1 is common for engines of the era, that's only a ball park to play in for finding what yours really likes best. The point of economy tuning is to reduce power efficiently when peak power is not required.

Thanks for posting your rpm range at different speeds, and using that with the log, I would block the range from 50 to 90 kPa, from 2000 to 4500, as your part-throttle economy-cruise test zone. We of-course tune one area at-a-time, and cruise is an easier stable area at this point, and the rest is 'running' OK for now.

Offhand, it looks like much of that higher-cruise area will need roughly 50+% leaning to just get into the economy cruise range. If you want to jump into the area, I would run VEA and MLV in that rpm/kPa block above, at 15.5:1, Hard, above 70° and 2k rpm on your last log. Go take a run, holding specific cruise speeds (50, 70, 90, 110 kph, or whatever) for a few minutes each for good data, and post the results. You should be in a closer range of economy AFRs at that point. You can then do some run-tests to find your lean limit to set your cruise AFR targets, then your lean ignition advance to make it safe and efficient. 8-)
#67060
@PSIG - Thanks for the comments. Engine is operating rich and drinking gas as if it were one of the main engines (P&W FT-4) on my last ship :D . Change the VE table cell values to lean out the engine but also changed out #4 cylinder fuel injector because #4 cylinder was fuel rich. My focus is on the area you mention.

I do a VEA after each road trial to consider possible changes, and review the data log in MLV. Still learning how to use MLV.

The AFRs you mention are quite lean, wouldn't have thought I should lean out that much. When I think about the fuel economy from this engine of 45 to 50 MPG (17-18 Km per litre) at cruise, solo or two up, these figures may be reasonable. I did notice that when the AFR/lambda readings were "leaner" the MAP reading was more around 60 KPa (when I could take my eyes ooff the road for a bit).

Had to figure out what you were mentioning about VEA '"in" MLV. I changed the AFR cell values and watched the VE analysis. VE table cell values reduced quite a bit.

Difficult to scan the tablet while driving.

Yes, it does drive. Weather has not been cooperating. Have an 80 Km route I use for road trials. Small changes will be done.

Here's todays tune and data log:
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