Stoich AFR setting in 8D (interesting)
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Joined: Sep 2000
Posts: 400
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From: Keller, Texas, USA
Car: Devastating Droptop
Engine: 355 Supercharged
Transmission: Auto 4L60, Built for 700hp
Stoich AFR setting in 8D (interesting)
I've playing around with the Romulator and the Stoich AFR setting in 8D aujp.bin using TunerCat.
While driving down the road at 2000rpm or at Idle I'm at 128blm with the Stoich AFR set at 14.5.
When I change the Stoich AFR setting to 15.5 my blm's climb to 140 and when I set the AFR setting back to 14.5 my bml's go back to 128.
the whole time my WBO2 is allways showing 14.4 to 14.7
the next thing I noticed and I'll verify latter, is that (when I changed my Stoich AFR setting to 15.5 and my blm's climb to 140 with the WBO2 still showing 14.6 ) the AFR did seem to lean out at WOT according to my WBO2.
It appears that This Stoich AFR setting dose do somthing I just not sure what. (Moves the BLM around)
Anybody have any thoughts on this and what might be its function.
While driving down the road at 2000rpm or at Idle I'm at 128blm with the Stoich AFR set at 14.5.
When I change the Stoich AFR setting to 15.5 my blm's climb to 140 and when I set the AFR setting back to 14.5 my bml's go back to 128.
the whole time my WBO2 is allways showing 14.4 to 14.7
the next thing I noticed and I'll verify latter, is that (when I changed my Stoich AFR setting to 15.5 and my blm's climb to 140 with the WBO2 still showing 14.6 ) the AFR did seem to lean out at WOT according to my WBO2.
It appears that This Stoich AFR setting dose do somthing I just not sure what. (Moves the BLM around)
Anybody have any thoughts on this and what might be its function.
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Joined: Jun 2000
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From: In reality
Car: An Ol Buick
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You also have to change the rich, lean O2 voltage settings, to match commanded AFR changes.
FWIW:
If you want to really get into lab grade work then your going to have to get into doing controlled testing, and/or accept close as good enough. The oems go thru all sorts of testing to verify things are as claimed, and once you leave the region of perfectly stock then your results are going to drift some from what you may expect, since you've moved from the actual design spec..
I've gone to 15.2, and as low as 13.2 changing the commanded AFRs, and O2 voltages set points. Gets time comsuming getting it all correct.
For off road use, open loop, works out better for me.
FWIW:
If you want to really get into lab grade work then your going to have to get into doing controlled testing, and/or accept close as good enough. The oems go thru all sorts of testing to verify things are as claimed, and once you leave the region of perfectly stock then your results are going to drift some from what you may expect, since you've moved from the actual design spec..
I've gone to 15.2, and as low as 13.2 changing the commanded AFRs, and O2 voltages set points. Gets time comsuming getting it all correct.
For off road use, open loop, works out better for me.
Thread Starter
Member
Joined: Sep 2000
Posts: 400
Likes: 2
From: Keller, Texas, USA
Car: Devastating Droptop
Engine: 355 Supercharged
Transmission: Auto 4L60, Built for 700hp
You also have to change the rich, lean O2 voltage settings, to match commanded AFR changes.
In Tunercat's 8D mask I only see o2 voltage settings for idle:
Threshold
Hysteresis
Upper zero error slow
Lower zero error slow
I guess there are settings for other than Idle ?
dose anybody no where they are in the aujp.bin
In Tunercat's 8D mask I only see o2 voltage settings for idle:
Threshold
Hysteresis
Upper zero error slow
Lower zero error slow
I guess there are settings for other than Idle ?
dose anybody no where they are in the aujp.bin
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Joined: Jul 1999
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From: Maryland
Car: 2005 Subaru STI
Engine: 153ci of Turbo Power!
Transmission: 6-Speed
Here's something I posted back on 9-25-2001
Tim
Interesting observations:
I thought to myself - hey, all I gotta do is change the stoich AFR from 14.7 to something higher and then go back and retest (they weren't checking NOx). Well, I set my stoich to 14.9, 15.1, and then 16.0 doing some testing in my driveway. This change did nothing to my car. The Base Pulse Width remained the same and the O2 voltage looked like 14.7 ... swinging back and forth as usual. The only way I could force my car to run lean is to force open loop via the Temp for closed loop enable and then reset the injector constant to something high (changed it from 33lb/hr to 40lb/hr). With open loop I was able to get the O2 voltage to drop down really low 30mV and lower. Also - the BPW with this setting was still the same as before (maybe single fire mode was engaged?).
I thought to myself - hey, all I gotta do is change the stoich AFR from 14.7 to something higher and then go back and retest (they weren't checking NOx). Well, I set my stoich to 14.9, 15.1, and then 16.0 doing some testing in my driveway. This change did nothing to my car. The Base Pulse Width remained the same and the O2 voltage looked like 14.7 ... swinging back and forth as usual. The only way I could force my car to run lean is to force open loop via the Temp for closed loop enable and then reset the injector constant to something high (changed it from 33lb/hr to 40lb/hr). With open loop I was able to get the O2 voltage to drop down really low 30mV and lower. Also - the BPW with this setting was still the same as before (maybe single fire mode was engaged?).
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