Mechanicals updated or repaired, new Datalog

#3 was my best flow guess flow adjustment based on ve % cross referencing your ve1 vs maf flow built into a histogram. I added the % to the maf flow curve then removed it from ve1 table. If I did not adjust a maf curve point then I had no data for it.

Changes in #2 and #3 differing is purposeful, never change too much at once, need to see the impact of one alteration at a time.
 
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Now lets look at some information from your tune file and latest datalog.
Blown88GT MAF CURVE issue.PNG
In My MLV, Histogram/Table Generator is greyed out.
It seems that this is only available in the HD version.
I purchased my MLV MS 5 years ago. Can upgrade to MLV HD for $19.95.
 
2. Blown88GT.REV.1.0.0.msq - small adjustments to idle strategy.
3. Blown88GT.REV.MAF RE-CURVE TEST 1.0.0.msq - large changes to MAF flow curve

Loaded #2, no dramatic difference.
Loaded #3, captured datalog at idle. Not much different from #2.
CurrentTune now at #2.

Sometimes a lot of oscillation right after throttle is blipped.
When backing up with steering wheel near lock, engine died during a datalog.
 

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  • Blown88GT.REV.MAF RE-CURVE TEST 1.0.0.msl
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  • Engine died while backing up.msl
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ok another round of small adjustments to the MAF curve on this one, I think the Brass screen did in fact make a difference the raw MAF input looks cleaner.
When the car stalled it almost looks as if the engine just died outright..
 

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Brass screen did make a positive difference.
It's not coming out, too much trouble getting it in.
AFR is lean during & after ASE.
RPM dropped very low & then it stalled.
This datalog was idling in the garage.

I still think using VE as trim is better.
Screwing around with an exponential curve is problematical.
 

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  • Blown88GT.REV.MAF RE-CURVE TEST 1.0.1.msl
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Last attempt to alter the MAF curve.... this time i built a field to change the MAF ADC input count to voltage so i could change the curve based on raw values...
I appreciate your patience with me on this experimental venture, I did my MAF alterations live so i could alter the curve a dot at a time... doing this with a datalog has proven to be very interesting!!
 

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  • Blown88GT.REV.MAF RE-CURVE TEST 1.0.2.msq
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Questions:
1. If I do any further tuning with VEAL, won't it modify only the VE Table?
2. Is there any way to take the changes made in the MAF curve, port them to the VE table & then change the MAF curve back to the stock curve?

My thinking is, limit all changes to the VE Table instead of both the MAF curve & the VE Table.
 
Questions:
1. If I do any further tuning with VEAL, won't it modify only the VE Table?
2. Is there any way to take the changes made in the MAF curve, port them to the VE table & then change the MAF curve back to the stock curve?

My thinking is, limit all changes to the VE Table instead of both the MAF curve & the VE Table.
I am making no changes to the VE table when I alter the file.
In a histogram I am plotting
X- rpm
Y- maf volts [(5/ 1023)*adc7 ] custom field
Z- afr error [(afr/afr target1)]

Using this information I am altering the maf curve based on afr% error to the maf g/sec.
Not sure if this is the right way to do it with a datalog yet but the next round of datalog info should tell the tale.
 
New round of datalogs
1st is startup & driving until ASE goes off.
2nd is pull over leave engine running & start another datalog until get back home.

In 1.0.2-2, look at datalog from 177s to 180s.
I get a stuttering or shuddering when accelerating in 2nd gear at 1/3-1/2 throttle from 1500 thru 2000 rpm & then it smooths out.

Should see multiple places with the same issue.
There seems to be a correlation with the AFR Target 1. It dips way down in this area.

I checked spark on all 8 with a timing light, all look the same at idle.
 

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  • Blown88GT.REV.MAF RE-CURVE TEST 1.0.2-1.msl
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  • Blown88GT.REV.MAF RE-CURVE TEST 1.0.2-2.msl
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Last edited:
New round of datalogs
1st is startup & driving until ASE goes off.
2nd is pull over leave engine running & start another datalog until get back home.

In 1.0.2-2, look at datalog from 177s to 180s.
I get a stuttering or shuddering when accelerating in 2nd gear at 1/3-1/2 throttle from 1500 thru 2000 rpm & then it smooths out.

Should see multiple places with the same issue.
There seems to be a correlation with the AFR Target 1. It dips way down in this area.

I checked spark on all 8 with a timing light, all look the same at idle.
Yes between 177 and 178 seconds i see the AFR go lean 15AFR during light to moderate load, the spark advance was low so i dont think that had anything to play into it personally.
This time i left the MAF curve alone, I think the huge VE numbers wont be seen again. I am also going to create a second fuel multiplier table for you this way you can tune for throttle position as well.
 

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  • Blown88GT.REV.MAF RE-CURVE 1.1.0.msq
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At the same time, Boost psi changes drastically.
However, Boost psi numbers make no sense; -12.6 to 1.1
It appears it could be the transition from vacuum to boost.

Lost power for a few hours this PM, mainline went out, probably a fuse to one of the phases.
It happens a lot here, old infrastructure & a lot of surrounding new construction.

Will try new tune tomorrow.
UPDATE:
Been raining all morning, no letup in sight.
 
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Beat the rain early this AM.
It's Getting Better All the Time...

BTW, the issue I'm having did not occur with the 30 lb injectors. Don't know the reason why.
 

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  • Blown88GT.REV.MAF RE-CURVE TEST 1.0.2-3.msl
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  • Blown88GT.REV.MAF RE-CURVE TEST 1.0.2-4.msl
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Been looking at your YouTube Tuning videos.
I see Part 1, Part 2 & Part 4.
What happened to Part 3?
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QUESTIONS:
1. BTW, how do I use Alpha-N (throttle position) to tune with VEAL?
2. Just set tab to Fuel VE Table 2?
3. Then start Auto Tune?
4. Why is TPS called Alpha-N? VE2 displays %TPS on the Y-axis.
5. Why do you think this is the best way to proceed?

Since Secondary Fuel is multiplicative & Tool Tip says:
With Alpha-N, enabling multiply MAP gives 'Hybrid Alpha-N' : disabling multiply MAP gives 'Pure Alpha-N'. MAF never multiplies in MAP.
6. This means that VE2 multiplies value in VE1? I edited X & Y axes of VE2 to match VE1; maybe not required, but easier for comparisons.