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ECMlink boost control table and automatic trans

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jpmxrider489

10+ Year Contributor
2,410
146
Apr 4, 2010
pittsburgh, Pennsylvania
I been trying to dial in the boost control table as I got my trans shifting better now via rpm. When I click the help icon, it says for autos, use the latest speed raw value. Am I supposed to change the gear ratio in the DA tab to match what latest speed is for the raw value? It seems like when I do the set boost tables, it wants to lower my target boost. Ill attach a log but I'm hoping someone can explain what values I need to match to what and the process to dial this in better. Log is pretty sloppy still. I'm trying to adjust this so when at the track I can just let the ecu and tcu do its thing. Also, I'm not sure how to match gear/boost when I don't think the ecu knows what gear I'm using. I'm hoping someone can guide me a little better on the correct process. In first gear, would like 17psi, 2nd gear is 23, and 3rd is all the boost.
 

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  • boost tables.elg
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I went through all this but dont remember what i set those at, let me see if i got an old log on my pc and go into ecmlink and see what i had that all adjusted to to get it right. Towards the end i was pretty good holding it to 25 and covering spikes to 27psi nicely. All logged well and boost was pretty smooth transition
 
Those links are very good and helpful. Those links are if im actually at the point of trying to control boost. I feel confident in my ability to do that aspect of it. My issue specifically is related to automatic transmission. I copied this from the wiki. If I understand, I need to use the formula to change the gear ratio in the DA tab. Now after doing that, I can adjust the boost table for each gear? Im hoping some auto guys will chime in to explain there process to adjusting all this. I think im starting to solve my own confusion here. But im hoping another nice day comes here in PA before winter. I want to work on this some more. I think my wggear ratio on the DA tab should be 21 for first and 41 for second and thats 25mph and then 50. So I believe first will be used for speed under 25. Second would be bettween 25-50mph. Finally, 3rd is anything above 50.

Use LatestSpeed for gear selection​

When this box is checked, the ECU will use vehicle speed instead of gear ratio to select the gear rows of the Boost Target and Base Duty Cycle tables. This is primarily provided for automatic transmissions where gear ratio isn't a reliable indication of gear due to the effect of the torque converter.

WGSGear - Direct Access Table​

When this box is checked, you'll want to change the WGSGear table in Direct Access on the WGSMisc tab. The default values are based on an internal (raw) ECU value named WGSGearRatio. If you want to base gear selection on speed instead, then you'll need to change this table to reflect values from the internal ECU variable named LatestSpeed. The following screen shot shows the WGSGear tab in direct access.
You must be logged in to view this image or video.

The values shown above are the default gear ratio values provided in ECMLink. These values would select Gear 1 when WGSGearRatio is below 158. Then it would select Gear 2 when WGSGearRtio is between 158 and 248. Then it would select Gear 3 anytime WGSGearRatio is above 248.
The ECU provides some internal hysteresis to limit sudden switching between gears.
To change these values to reflect speed instead, calculate your speed points as:
WGSGear value = (speed in mph) / 1.2425
So, for example, if you want to select 2nd gear at 40mph, you will use 32 as the Gear 1 value. If you want to select 3rd gear at 80, then you'll use 64 as the Gear 2 value.
You can also display the raw ECU value called LatestSpeed on your graph using the Raw value → button in the Display Values dialog. That's the value the ECU will compare against when doing gear selection based on speed. You can use those values directly in the WGSGear table.
 
Those links are very good and helpful. Those links are if im actually at the point of trying to control boost. I feel confident in my ability to do that aspect of it. My issue specifically is related to automatic transmission. I copied this from the wiki. If I understand, I need to use the formula to change the gear ratio in the DA tab. Now after doing that, I can adjust the boost table for each gear? Im hoping some auto guys will chime in to explain there process to adjusting all this. I think im starting to solve my own confusion here. But im hoping another nice day comes here in PA before winter. I want to work on this some more. I think my wggear ratio on the DA tab should be 21 for first and 41 for second and thats 25mph and then 50. So I believe first will be used for speed under 25. Second would be bettween 25-50mph. Finally, 3rd is anything above 50.

Use LatestSpeed for gear selection​

When this box is checked, the ECU will use vehicle speed instead of gear ratio to select the gear rows of the Boost Target and Base Duty Cycle tables. This is primarily provided for automatic transmissions where gear ratio isn't a reliable indication of gear due to the effect of the torque converter.

WGSGear - Direct Access Table​

When this box is checked, you'll want to change the WGSGear table in Direct Access on the WGSMisc tab. The default values are based on an internal (raw) ECU value named WGSGearRatio. If you want to base gear selection on speed instead, then you'll need to change this table to reflect values from the internal ECU variable named LatestSpeed. The following screen shot shows the WGSGear tab in direct access.
You must be logged in to view this image or video.

The values shown above are the default gear ratio values provided in ECMLink. These values would select Gear 1 when WGSGearRatio is below 158. Then it would select Gear 2 when WGSGearRtio is between 158 and 248. Then it would select Gear 3 anytime WGSGearRatio is above 248.
The ECU provides some internal hysteresis to limit sudden switching between gears.
To change these values to reflect speed instead, calculate your speed points as:
WGSGear value = (speed in mph) / 1.2425
So, for example, if you want to select 2nd gear at 40mph, you will use 32 as the Gear 1 value. If you want to select 3rd gear at 80, then you'll use 64 as the Gear 2 value.
You can also display the raw ECU value called LatestSpeed on your graph using the Raw value → button in the Display Values dialog. That's the value the ECU will compare against when doing gear selection based on speed. You can use those values directly in the WGSGear table.
Great explanation - You just helped me learn what that latest speed checkbox does
 
I have a manual so I can’t help you too much but It seems you have it under control now by switching it to latest speed instead of the gear. I also seen you said another nice day in PA. Lol I’m in south central pa and we have about 2 inches of snow on the ground now and it’s still going…….damn PA. Idk why I still live here.

-Daniel
 
I have a manual so I can’t help you too much but It seems you have it under control now by switching it to latest speed instead of the gear. I also seen you said another nice day in PA. Lol I’m in south central pa and we have about 2 inches of snow on the ground now and it’s still going…….damn PA. Idk why I still live here.

-Daniel
Ya, the snow just came down where im at.

Great explanation - You just helped me learn what that latest speed checkbox does

I'm slowly getting the hang of it but was hoping for input from auto guys. Mainly about how to combine data from dsmlink and work with the tcu. I want to know kind of a step by step on how to go about tuning so all I got to do is mash the throttle at the light. I got the tcu shifting much better. However, the dsmlink side of controlling boost and gears is different. Also in the DA tab, should I be adjusting the values under the gear ratio? I definitely understand the concept with your links. Now are you just setting boost values in the rpm range for the gear?
 
Now are you just setting boost values in the rpm range for the gear?
Excellent question - No I do not use the PSI table in actual use because I turned off error correction.

The PSI values I did punch in reflect what I believe the duty cycles are producing (from logs). If I understand how it works, turning on error correction would apply a factor on top of the duty cycle to try and hit the PSI target - but I have not seen it working better than leaving error correction off. I guess I just got used to working in duty cycles.
 
Excellent question - No I do not use the PSI table in actual use because I turned off error correction.

The PSI values I did punch in reflect what I believe the duty cycles are producing (from logs). If I understand how it works, turning on error correction would apply a factor on top of the duty cycle to try and hit the PSI target - but I have not seen it working better than leaving error correction off. I guess I just got used to working in duty cycles.
So based on what you just said, error correction is used if your surging or spiking then? My theory was to try and set my boost target for a given rpm, then see how much error correction it does. Then add or subtract that error correction from the current duty cycle. Is that not the right way? Maybe better to use only duty cycle then only use correction if there is a issue? So the table in the Direct Access where gear ratio is, you left that stock?

Also, for a manual you did adjust the gear ratio? If so, why and what variables did you use to get the number? This is kind of unrelated to my auto related thread but this thread has some helpful info.
 
I will charge my laptop up in hopes it displays my last settings. My last log does not show my current finished boost table for some weird reason.

When i started this i adjusted the speed also but then found conflicting info on the ratios so i reset them and stopped using that and just made my own adjustments to what i saw vs revs and speed. I found this was at the end a better way vs allowing the ecu to do the work. I guess if it was setup properly its actually much simpler vs each box being adjusted but saying that i now have full control and can ramp down the boost on low gears where its not needed vs rpm based where even then it will try give you full whack at the time it can.
I like the gradual boost and its more useable and spikes are now well controlled. I can spike to 27psi but as i let it its ok and i know its there.
 
My theory was to try and set my boost target for a given rpm, then see how much error correction it does. Then add or subtract that error correction from the current duty cycle. Is that not the right way?
That is logical, I would try that.
also, I did not adjust the gear ratio because WG gear was reporting the gear i was in correctly.
 
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