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6E tuning for lean condition

Old Feb 20, 2020 | 07:20 AM
  #51  
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Re: 6E tuning for lean condition

It’s my plan b
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Old Feb 20, 2020 | 07:23 AM
  #52  
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Re: 6E tuning for lean condition

Also maybe check some spark plugs to see if they seem lean as well. May need some fresh ones and put some cruise miles on where its lean and see what it looks like
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Old Feb 20, 2020 | 07:35 AM
  #53  
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Re: 6E tuning for lean condition

I took out a couple from each side and they all seem to be whiteish... / brownish. Definitely not black but will change them once I get these tests out of the way.
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Old Feb 21, 2020 | 12:10 PM
  #54  
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Engine: 350 TPI
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Re: 6E tuning for lean condition

I went to try if the change in Offset vs Coolant in the O2 tables made a difference... It didnt.
I also fiddled around with the other O2 tables (R/L, Upper and Lower) by adding even 50%!!! in steps of 10%. AFR bulged only a 0.2 if at all..

So I threw the towel, set it permanently as Open Loop and I could see the beauty of MAF Tables where during emulation I could immediately see the AFR reflecting the changes. I managed to get around 14.3AFR in the first 3 tables (till circa 80 Grams) and circa 13 - 12 AFR in the other tables. Now I came home and noticed that MAF tables 2 and 3 had the last 3x rows maxed out so I increased the scalars by 1 and 2 respectively and smoothed out the tables and overlap across tables.

Will try to give it another run this weekend to see if the smoothing but overall at last I am seeing some improvement. For sure idles feels much more stable as previously during CL it was at around 16 - 16.3 now it is at 14.4.... It even sounds better and I might decrease a bit the idle now.
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Old Aug 28, 2021 | 02:46 PM
  #55  
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Re: 6E tuning for lean condition

Finally found someone with the same exact problem as me!! I decided to go back to maf. Since in cali. I’m running the same lean AFR. Plugs are looking like running lean, my AFR is lean on the wideband. And tried raising my o2 constants considerably. But I raised them so high it just sets the CEL just to get it close to what I need. I’m running the superram, 219 cam , AFR 180 heads, long tube hedman headers, didn’t matter if I used heated o2 or stock non heated. Tried both. Looks like I finally found my answer. Guess I need to run open loop. This is on a corvette though.
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Old Aug 28, 2021 | 06:19 PM
  #56  
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Re: 6E tuning for lean condition

Originally Posted by Kitttransam
Finally found someone with the same exact problem as me!! I decided to go back to maf. Since in cali. I’m running the same lean AFR. Plugs are looking like running lean, my AFR is lean on the wideband. And tried raising my o2 constants considerably. But I raised them so high it just sets the CEL just to get it close to what I need. I’m running the superram, 219 cam , AFR 180 heads, long tube hedman headers, didn’t matter if I used heated o2 or stock non heated. Tried both. Looks like I finally found my answer. Guess I need to run open loop. This is on a corvette though.
I understand what you are going through. With my hotcam, fastburn heads, pro-flo, EBL with MAP, I never was happy under 1500 rpm's in closed loop. I run strictly open loop, AFR 13.8 -14 at idle and taper to 14.7 over 1500. It runs great from idle to 6200 when I hit the rev limiter. I don't have to pass emissions so I see no advantage of going back to closed loop. A perfect open loop tune takes lots of data logging and small changes to perfect but it is worth it.
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