Evolution of a AutoVE Tune

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July 9th, 2009
kwhiteside

Evolution of a AutoVE Tune

So I'm cycling thru the AutoVE process. Make a run, log it, get the BEN/Map recommended changes and multiply them to the VE table. Repeat the process.

I must admit, I barely unstand what I'm doing as I go through the motion of the tutorial from a engine standpoint, but now that I have some data, I'm starting to see what is happening.

The Tutorial starts by increasing the Kpa numbers by 15% across the table. Richening things up for protection. As you drive and log, the process makes real world changes to the table, bringing those numbers into line with reality, usually lower. Best case scenario, you would get real world number for every cell in your VE table. Seems that isn't going to ever happen, and this is the cause for the Rocky Mountains that many have complained about. Especially at the high RPM's where you car doesn't usually go there but for a quick moment.

In the image below, you see the graph of the mountains and valleys and the cells causing the affect. These cells started out with much higher values per the tutorial, the the logging process makes real world changes to only some of the cells.

http://downloads.dataxperts.net/rockymountains.png

In the image below you see on the top my original tune. The middle tune had the 15% tacked on, and then the real world changes from a spirited run around town. The bottom tun is after 4 iterations of this process. Note the highlighted cells in across the 3 tunes.

They start in the original tun with

83
85
91

Tutorial process pumps them up with some fuel to much higher values and they start working down

90
90
94

Now actually leaner than my original tune from many real world iterations.

79
81
86

http://downloads.dataxperts.net/Evolution.png

My theory here is that the huge valleys created are actual real world reading from the cells that are getting hit. The peaks are not getting hit (enough anyway) so no adjustments are being made to them. So in theory, the valleys are correct, and the peaks should be leveled off to match the cells that had valid real world readings. Anybody disagree with that theory, please explain if you do.
July 9th, 2009
joecar

You could level out the peaks to almost blend with the valleys, and then do another iteration.
July 9th, 2009
kwhiteside

I flashed it a few minutes ago. If I get it started, I'll get a good log on the way home and see how close it is now.
July 9th, 2009
joecar

See the other thread.
July 9th, 2009
waterbug1999

How long did you log?
July 10th, 2009
mr.prick

Open Loop tuning on the streets sucks.
You can log, filter, paste and smooth all you want but {B0101}
will not be consistent at all temperatures, altitude and even load in OLSD.
You can get a general shape for the VE table this way then enable LTFTs
and tune with them for non PE areas.
When PE is on and LTFTs are 0%, you can use WBO2 to adjust the WOT areas.
No smoothing has been done to this VE table and LTFTs are between 0% and -3%
http://i235.photobucket.com/albums/e...spar/B0101.jpg
July 10th, 2009
kwhiteside

Open Loop Speed Density mode VE Table

Well my VE table isn't as nice as your but after about 6 logs and tweaks, my AFR and commanded are dead on, and my Ben/Map barely recommends any changes to my VE table. This is what I ended up with, and I've turned the MAF back on. I'll have to figure out how to tune that now!

http://downloads.dataxperts.net/b0101.png

Oh, BTW, when doing street logging. I've discovered that during low volume traffic, you can find some good on ramps that have about the same function as a 1/4 mile dragstrip. Get off and on the highway a few times and you have some really nice full throttle red line logs!
July 10th, 2009
mr.prick

How did you go from post #1 to post #7?
I seem to have missed the point of this thread. :doh2:
July 10th, 2009
kwhiteside

Quote:

Originally Posted by mr.prick

How did you go from post #1 to post #7?
I seem to have missed the point of this thread. :doh2:

I followed the process and tested my theory over and over until I achieved the desired result as shown in my VE Graph progression from post 1 to post 7.

The thread was to show those people who don't like the AutoVE tuning process because it leaves the VE table looking like the rocky mountains that with a little more process, it can be smooth and a great baseline.

To repeat the theory. The tutorial has you pump up the gas in the VE table which creates the high mountains. Then real time logging and Ben/Map tweaking starts creating the valleys. The real time stuff is right on, so smooth it out to match the cells you do get. Use the interpolation spreadsheet, then go ahead and tweak manually the cells that you most likely will never hit. Do some more logging until you find the recommended changes from the Ben/Map are barely visible anymore.
July 10th, 2009
joecar

Your VE table from post #7 is quite good (maybe a little too smooth, check your BEN's now).

Quote:

Originally Posted by kwhiteside

...
The tutorial has you pump up the gas in the VE table
...

Some notes:
VE table is a normalized airmass table (normalized for temperature and pressure), its units are g*K/kPa (not %).
PCM uses VE table (and/or MAF table) to compute cylinder airmass;
PCM then looks up AFR from richer of OL fuel table or PE table (if PE enabled) in OL, or uses stoichiometric AFR in CL;
PCM then computes fuelmass required to meet that AFR;
PCM then looks up IFR table and computes the injector pulsewidth required to deliver that fuelmass.

So increasing the VE table (or the MAF table) increases the fuelmass (in an indirect manner), just be aware of this.
July 10th, 2009
kwhiteside

I'm driving home AutoMAF, instead of AutoVE. MAF enabled, b0120 set to 400, b3801 disabled, MAFFREQ added to my BBL PID's. I'm actually quite scared to do it, but am going to give it a try. I'm sure I'll be starting an new thread later this evening.
July 10th, 2009
edwardzracing

Quote:

Originally Posted by mr.prick

Open Loop tuning on the streets sucks.
You can log, filter, paste and smooth all you want but {B0101}
will not be consistent at all temperatures, altitude and even load in OLSD.
You can get a general shape for the VE table this way then enable LTFTs
and tune with them for non PE areas.
When PE is on and LTFTs are 0%, you can use WBO2 to adjust the WOT areas.
No smoothing has been done to this VE table and LTFTs are between 0% and -3%

Not trying to highjack the thread, I just wanted to ask mr. prick a quick question. Do you have any links or could you maybe send me a message on tuning with LTFT's? You make mention of it in this post, and I thought I'd ask for some guidance or advice. Would I be able to use the map included with EFILive entitled {B0101} Main VE - LTFT Bank 1.map? Then make changes as needed after doing an AutoVE and then re-enabling LTFT's? Any help would be appreciated. Thanks.
/end highjack.
July 10th, 2009
WeathermanShawn

Depending on your modifications 'AutoMAF' may work out pretty good. You might have some fueling problems at idle. If you have any cam (other than stock), the overlap at idle can cause 'reversion' and both your wideband and narrowband O2 sensors will not be accurate.

For the other poster on LTFT's. Sometimes mapping them becomes easier if you change all of the narrowband O2 switch-points (B4105) to say 500mv.
July 10th, 2009
mr.prick

1 Attachment(s)

Tuning with LTFTs and WBO2

Assuming your exhaust has no leaks and WBO2 is configured/working properly:
1. Set up Closed Loop Speed Density (no DFCO or catalytic converter protection)
2. Set the O2 switch point {B4105} to 450.0mV
3. DO NOT DISABLE PE

Create CALC.PID

PHP Code:

#Units Low High Fmt Expression #------------ ------ ------ ---- ------------------------------------------- *CLC-00-010 factor 0.0 1.4 0.2 "({SAE.LONGFT1}+{SAE.LONGFT2})/2/100+1" #Code PRN SLOT Units System Description #---------------- ---- ------------ --------- ---------- ------------------- CALC.LTFTBEN F010 CLC-00-010 factor O2-Wide "LTFT BEN"

Log PIDs (minimum)
CALC.LTFTBEN
GM.AFR
GM.DYNCYLAIR_DMA
GM.KR
SAE.ECT
SAE.IAT
SAE.LONGFT1
SAE.LONGFT2
SAE.MAP
SAE.RPM
SAE.SPARKADV
SAE.TP
Add relevant WBO2 PIDs ect.

Attachment 5950
Exclude data frames
SAE.TP.% changing more than 5% 100ms OR
GM.AFR.:1 is less than 14.6{B3601} OR
SAE.ECT.F is less than 180°F

Paste LTFTBEN to {B0101}

Enable the edit mask and shield the cells changed by LTFTBEN.

Then for WOT/PE mode Exclude data frames
SAE.TP.% changing more than 5% 100ms OR
GM.AFR.:1 is greater than 14.6 (a little under {B3601}) OR
CALC.LTFTBEN is not equal to 1.00 OR
SAE.ECT.F is less than 180°F
Paste BEN to {B0101}

Reflash and reset LTFTs.

Tuning with LTFTs will take a little more time because a higher cell count
is needed for the PCM to learn LTFTs.

*Average LTFT PID

PHP Code:

#Units Low High Fmt Expression #---------- ----- ------ ---- ---------------------------- *CLC-00-004 % -100 99.22 0.2 "({SAE.LONGFT1}+{SAE.LONGFT2})/2" # ============================================================ #Code PRN SLOT Units System Description #------------- -------- --------- ----- ---------- ---------------- CALC.LTFT F004 CLC-00-004 % Fuel "LTFT Average"
July 10th, 2009
The Alchemist

Thats a great effort for a Auto VE tune done on the road. Well done mate!! :cucumber:

Mike

Quote:

Originally Posted by kwhiteside

Well my VE table isn't as nice as your but after about 6 logs and tweaks, my AFR and commanded are dead on, and my Ben/Map barely recommends any changes to my VE table. This is what I ended up with, and I've turned the MAF back on. I'll have to figure out how to tune that now!

http://downloads.dataxperts.net/b0101.png

Oh, BTW, when doing street logging. I've discovered that during low volume traffic, you can find some good on ramps that have about the same function as a 1/4 mile dragstrip. Get off and on the highway a few times and you have some really nice full throttle red line logs!
July 11th, 2009
mr.prick

This looks suspiciously like a stock C5 ZO6 VE. :sneaky:
July 11th, 2009
nevinsb

I would agree, STFT tuning is the way to go, maybe after 1 round of wideband AutoVE to whack it into shape.
July 11th, 2009
joecar

Quote:

Originally Posted by mr.prick

This looks suspiciously like a stock C5 ZO6 VE. :sneaky:

He did start with a stock Z06 file... if you look closely you will see there are some differences... his mods are intake/headers.
July 13th, 2009
kwhiteside

Quote:

Originally Posted by mr.prick

Assuming your exhaust has no leaks and WBO2 is configured/working properly:
1. Set up Closed Loop Speed Density (no DFCO)
2. Set the O2 switch point {B4105} to 450.0mV
3. DO NOT DISABLE PE

Create CALC.PID

PHP Code:

#Units Low High Fmt Expression #------------ ------ ------ ---- --------------------------------------------------------------------------- *CLC-00-010 factor 0.0 1.4 0.2 "({SAE.LONGFT1}+{SAE.LONGFT2})/2/100+1" #Code PRN SLOT Units System Description #---------------- ---- ------------ --------- ---------- ------------- CALC.LTFTBEN F010 CLC-00-010 factor O2-Wide "LTFT BEN"

Log PIDs (minimum)
CALC.LTFTBEN
GM.AFR
GM.DYNCYLAIR_DMA
GM.KR
SAE.ECT
SAE.IAT
SAE.LONGFT1
SAE.LONGFT2
SAE.MAP
SAE.RPM
SAE.SPARKADV
SAE.TP
Add relevant WBO2 PIDs

Filter out:
SAE.TP.% changing more than 5% 100ms OR
GM.AFR.:1 is less than {B3601}

Paste LTFTBEN to {B0101}

Enable the edit mask and shield the cells changed by LTFTBEN.

Then for WOT/PE mode filter out:
SAE.TP.% changing more than 5% 100ms OR
GM.AFR.:1 is greater than 14.62 or just under {B3601} OR
CALC.LTFTBEN is not equal to 1.00
Paste BEN to {B0101}

Reflash and retset LTFTs.

Notes:
1. Tuning with LTFTs will take a little more time because a higher cell count
is need for the PCM to learn LTFTs.
2. LTFTs between 0% and -5% are the target but 0% to -3% is obtainable.
3. Don't alter cells where average LTFTs* are between 0% to -3%.
4. You want LTFTs to be 0% or negative before entering PE.

Average LTFT PID

PHP Code:

#Units Low High Fmt Expression #---------- ------------- ------------- ---- ---------------------------- *CLC-00-004 % -100 99.22 0.2 "({SAE.LONGFT1}+{SAE.LONGFT2})/2" # ============================================================ #Code PRN SLOT Units System Description #------------- -------- --------- ----- ------------------ ---------------- CALC.LTFT F004 CLC-00-004 % Fuel "LTFT Average"

First off let me say, yet another completely new concept (Tuning by LTFT). Every time you guys speak its something new. Thanks for the continual enlightenment.

That said and having recently learned the the main VE table only takes you to 4k in real life, the VE table will not be very important at the track, but will be important around town. So if I'm running ok in VE mode around town without my MAF ( and I was running awesome ), why bother tweaking it more with the LTFT?

My main goal is running strong and safe at the track, which is mostly high rpm, doesn't that make what my MAF does most important to me?

BTW, I have not done any AutoMAF runs yet as I hit a wall with my ignition switch and had to refurbish it. Hopefully I'll be good to start again tonight after I put my dash and console back together. The contact points were all burned up inside and causing starting problems and the car actually shut off Fri on the way home.