AFR target table
AFR target table
Can you change the load axis of the afr target table to something else then what the main load is using?
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Re: AFR target table
Middle-left says "Use TPS instead of Load"
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Re: AFR target table
My bad. No, that we do not have.
It would be a trivial checkbox to add but is that a useful checkbox?
It would be a trivial checkbox to add but is that a useful checkbox?
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Re: AFR target table
OK, you got me curious, what are you planning to do that would need the afr target decoupled from the ve table and other fueling?
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Re: AFR target table
I never said decoupled from the ve table. The AFR table still sets the fueling you want. Just because I am in boost doesn't mean I want to add fuel. Maybe I'm at 7psi of boost at 3000 revs but want Lambda 1 and not .8. likewise if I am at 100% throttle I want my lambda at .8.OrchardPerformance wrote: ↑Mon Aug 31, 2020 1:34 amOK, you got me curious, what are you planning to do that would need the afr target decoupled from the ve table and other fueling?
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Re: AFR target table
OK I see, so its more a case of being able to overide the afr table to do power enrichment above a certain tps point.
That makes sense.
For clarity, using the afr table to tune the labmda for normal running conditions and run lamdba one everywhere you don't have to use rich mixture for cooling (like an oem does) but still be able to run 0.8 lambda at full throttle.
I can see this being possible with one of the fsio tables as a lambda traget modifier but I do wonder if this also brings a requirement modify the ignition timing too
That makes sense.
For clarity, using the afr table to tune the labmda for normal running conditions and run lamdba one everywhere you don't have to use rich mixture for cooling (like an oem does) but still be able to run 0.8 lambda at full throttle.
I can see this being possible with one of the fsio tables as a lambda traget modifier but I do wonder if this also brings a requirement modify the ignition timing too
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Re: AFR target table
I think this way of handling fuel (driver demand based, essentially) is a great idea. I'd do a similar thing on my skyline as it's entirely possible to get a couple pounds of boost at 3000RPM at 15% throttle going up a hill - and I have no desire to be at .8 there. Being able to modify or otherwise change ignition timing based on AFR target would be required to maximize the benefit from having different lambda targets. You could also use this same workflow for lean-cruise, i.e. pump in a bunch of timing at low loads when targeting 1.1-1.2 lam.
I would suggest:
-Maximum lambda vs. load (to make sure that you get some enrichment when you get high loads at part throttle)
-Target lambda vs driver demand (to get more power from engine when driver asks for it, to get lean cruise when driver asks for it)
-Modify timing based on load and lambda target (to get timing and fuel on same page in terms of desired behavior)
I would suggest:
-Maximum lambda vs. load (to make sure that you get some enrichment when you get high loads at part throttle)
-Target lambda vs driver demand (to get more power from engine when driver asks for it, to get lean cruise when driver asks for it)
-Modify timing based on load and lambda target (to get timing and fuel on same page in terms of desired behavior)
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Re: AFR target table
So why not just leave the AFR target table at stoich up as far as you want? You won't be at 120kpa anyway when wide open, so why gate AFR on throttle instead of MAP?
Re: AFR target table
Re: AFR target table
Its more of the case of being able to use a VE based ecu correctly. The VE map shouldn't be used to deal with fueling. It should be used to map the airmass though the engine and any fueling changes should be allowed to be done however the user wants. The whole point of VE tuning becomes moot if the commanded fuel table is locked in terms of load and rpm.OrchardPerformance wrote: ↑Mon Aug 31, 2020 9:52 amOK I see, so its more a case of being able to overide the afr table to do power enrichment above a certain tps point.
That makes sense.
For clarity, using the afr table to tune the labmda for normal running conditions and run lamdba one everywhere you don't have to use rich mixture for cooling (like an oem does) but still be able to run 0.8 lambda at full throttle.
I can see this being possible with one of the fsio tables as a lambda traget modifier but I do wonder if this also brings a requirement modify the ignition timing too
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Re: AFR target table
Can you elaborate on how you would do what you are requesting?hentai wrote: ↑Fri Sep 04, 2020 4:59 amIts more of the case of being able to use a VE based ecu correctly. The VE map shouldn't be used to deal with fueling. It should be used to map the airmass though the engine and any fueling changes should be allowed to be done however the user wants. The whole point of VE tuning becomes moot if the commanded fuel table is locked in terms of load and rpm.OrchardPerformance wrote: ↑Mon Aug 31, 2020 9:52 amOK I see, so its more a case of being able to overide the afr table to do power enrichment above a certain tps point.
That makes sense.
For clarity, using the afr table to tune the labmda for normal running conditions and run lamdba one everywhere you don't have to use rich mixture for cooling (like an oem does) but still be able to run 0.8 lambda at full throttle.
I can see this being possible with one of the fsio tables as a lambda traget modifier but I do wonder if this also brings a requirement modify the ignition timing too
What would be your suggestion of the way to do it correctly?
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Re: AFR target table
For cable throttle:
1. VE table for airflow and just airflow.
2. Pressure vs. maximum lambda (leanest allowable commanded) Why? So you don't end up at 1.1 lam @ 220kpa @ 3000 RPM on a small-turbo car
3. TPS vs RPM for power enrichment mode enable
4a. Power enrichment: RPM vs target lambda table, pressure compensation for target lambda in PE, possibly minimum lambda setting to avoid over-richening?
OR
4b. Power enrichment: RPM vs. Load (outright pressure, grams/cyl, etc. Pick your poison) with table values = target lambda
For DBW, a torque based system makes sense.
1. VE table for airflow and just airflow
2. Pressure vs. maximum lambda to limit how lean you can be
3. TPS vs. RPM vs. desired torque
4. Torque calculation from airflow, modify for lambda, modify for distance from MBT timing, modify for vcam.
1. VE table for airflow and just airflow.
2. Pressure vs. maximum lambda (leanest allowable commanded) Why? So you don't end up at 1.1 lam @ 220kpa @ 3000 RPM on a small-turbo car
3. TPS vs RPM for power enrichment mode enable
4a. Power enrichment: RPM vs target lambda table, pressure compensation for target lambda in PE, possibly minimum lambda setting to avoid over-richening?
OR
4b. Power enrichment: RPM vs. Load (outright pressure, grams/cyl, etc. Pick your poison) with table values = target lambda
For DBW, a torque based system makes sense.
1. VE table for airflow and just airflow
2. Pressure vs. maximum lambda to limit how lean you can be
3. TPS vs. RPM vs. desired torque
4. Torque calculation from airflow, modify for lambda, modify for distance from MBT timing, modify for vcam.
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Re: AFR target table
I would completely make use of the PE vs. non-PE modes on my RB20DET skyline because it's so easy to make boost at low throttle angles going up a hill.
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Re: AFR target table
now tracked on github: https://github.com/rusefi/rusefi/issues/1761
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Re: AFR target table
this is now done for VE and AFR, i.e. the ask of this threadmck1117 wrote: ↑Sun Sep 06, 2020 8:25 amnow tracked on github: https://github.com/rusefi/rusefi/issues/1761
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