new to autoVE tuning

[noobtuner]

Hey guys,
currently playing around with a vy commodore and doing a maffless tune. Following the autoVE tutorial all the way until we are logging BEN values. I have a couple of questions.

1. i understand how the EQ ratio is proportional to AFR, but how. Lambda and EQ ratio are slightly out?

2. if you try to get an EQ ratio of 1.00 +/-.01 all over the BEN graph, doesnt that make top end and under load a tad lean. I do not understand the reason for making the BEN graphs values 1.00 all over the graph?

3. After data logging, it may be .07 +/- out in some spots, do i keep on pasting and multiplying the BEN table to VE table. THats what i read in the tutorial and if i do, it changes the values too much.

4. whats the minimum cell count you can use, i dont like the idea of holding th e motor at such high revs. How do you guys map 4000rpm upwards.

I know i have asked alot, and any help would be greatly apreciated,
thanks Julian
using v7 software with v2scan

[hquick]

I'll try to answer some of these...as I understand it.
1...not sure..sorry. One thing..higher than 1 in EQ means rich (1 being stoich)
Higher than 14.7 in AFR means lean....14.7 being stoich.

2. You're not trying to get an EQ of 1 all over the graph. The Ben factor is basically when you're trying to get the commanded fuel to match the actual fuel as measured via a wideband O2 sensor.
So...if you command 14.7...the WBO2 should read 14.7AFR. This is a BEN factor of 1.0.
So...by getting all 1's you're just making the logged AFR equal the commanded AFR.
It doesn't matter whether or not PE is enabled...infact...I believe you should keep it enabled so you don't go lean under higher load.
If you command an AFR of 12.5 under PE and your WBO2 reads 12.5...it's still a BEN of 1.0.
3. As you get closer to the 1.0 magic number....you may need to tighten your filters.
4. Min cell count....I sometimes use 50+ for the cells I hit ALOT.
For others which I rarely hit....I might only use a cell count of 5-10.

[joecar]

Julian,

Welcome to the forum...:cheers:

EQ = stoich/AFR = 1/Lambda

Where stoich is defined in B3601, can be 14.63 or 14.68.

[joecar]

Julian,

BEN = measured_AFR/commanded_AFR = commanded_EQ/measured_EQ

BEN is not EQ;
BEN is the ratio of how close the measured and commanded AFR's or EQ's are
BEN == 1.00 means they are equal.

Cheers,
Joe
:cheers:

[joecar]

To get cell hits above 4000 rpm, set the min cell count lower as Howard said.

[TAQuickness]

Welcome to the forum Julian. Looks like the guys have answered your questions. Please feel free to post up any other questions you may have.

[hquick]

Oh...and I set my commanded to 14.45 where it would normally be 14.63 to ensure no rounding and ending up with trims active.

[noobtuner]

thanks for the help guys. Will play around with it today. im sorry for such stupid qestions. Higher up in the rev range, is it all right to log only like every two cell, and then smooth out the VE table? So it is alright to keep on copying the BEN table to the VE table to try to get closer to one. I will tighten the filters up and try that, because when i did copy and paste it after the second log, it would change the values by .07+/-.
Cheers Julian.

[hquick]

No such thing as a stupid question. Stupid is to not ask...and blow something up!
This is what I do...right or wrong...don't know but it seems to work.
During a log I try to hit as many cells as possible at steady state driving (difficult in built up traffic).
Sometimes I'll drive down some back roads at really low speed...like barely out of idle and I just try to hit the low Kpa/RPM cells.
On the freeways I try to hit the higher RPM cells and then push into boost for small amounts of time at different RPM levels. I watch my boost guage (because it's infront of me...laptop is on the passenger seat). I try to make the boost guage needle sit at certain points for as long as possible.
Once done....I apply my filters so...EXCLUDE the following:
TPS less than 0.5% (to remove decel)
TPS varying by more than 5%
IAT's lower than 40oC (my normal running temps are around 50oC)
ECT's lower than 68.8oC (normal is around 75 for me in this weather)
KPA more than 105.5
I then look at the cell count.
If it was a new tune...I might do the first run at 10 cells or more (so set empty cells to 10).
That should get within the ballpark.
I then remove filters and empty cell countfrom the log and take another look at the raw data.
I look at the decel cells and if rich I'll do a copy with labels/paste and multiply with labels..then I 'guess' and pull the cell adjustment back a touch. Eg, If I do the paste and a cell changes from 60.0 to 55.0 because it was running rich on decel...I'll then change that to say...57.5. I do this so as to not keep 'overshooting' the mark and going back and forth. I'd rather sneak up on the 'magic 1.0'.
I then look at area's where I've hit cells in a row and have missed some in between on the same line. I just adjust those 'inbetween' cells along the same lines as the cells either side.
Then....I run another log...and do it all again. So far....750 plus logs...and still not happy.
My truck is 'unique' though...and I think I'm just a little OC (never used to be...before EFILive :laugh: ).
Hey...anyone else can steer me toward a better way...I'm happy for the constructive criticism.

[joecar]

What Howard said: the stupid questions are the ones that were never asked.

:cheers:

[5.7ute]

noobtuner welcome to the forum.
It wouldnt hurt to post your tune file & log on here while learning so the guys can have a look. There have been a few mistakes that myself & others have made that if not for this forum would have gone uncorrected, and possibly caused damage.

[noobtuner]

thanks for the replys. I am going to load the orginal tune and log again. But if the BEN table is out .07+/- in some areas, is it alright to paste and multiply (after strict filtering of course) it to the VE table. Is that how u get the EQ ratio 1?
Thanks Julian

[hquick]

yes....not EQ ratio...BEN factor!

[5.7ute]

The purpose of AutoVE is to get your actual AFR (measured by the wideband) to equal your commanded AFR ( commanded from B3605 (B3647 if a custom os) or B3618 whichever is richer)
However what you are reading in the BEN map is the factor needed to multiply to the VE table to get actual = commanded AFR. So a BEN factor of 1.0 meens no change is necessary. A factor of 1.07 means the cell needs increasing 7% or a factor of 0.93 means the cell needs reducing by 7%.
Dont confuse this with EQ ratio which is actually the Air Fuel Ratio from Stoich (14.63)

[noobtuner]

The purpose of AutoVE is to get your actual AFR (measured by the wideband) to equal your commanded AFR ( commanded from B3605 (B3647 if a custom os) or B3618 whichever is richer)
However what you are reading in the BEN map is the factor needed to multiply to the VE table to get actual = commanded AFR. So a BEN factor of 1.0 meens no change is necessary. A factor of 1.07 means the cell needs increasing 7% or a factor of 0.93 means the cell needs reducing by 7%.
Dont confuse this with EQ ratio which is actually the Air Fuel Ratio from Stoich (14.63)

yer sorry, i understand we are tying to get a ben factor of one. So if its 7% out, do you past and multiply the 1.07 in the ve table and by doing that, when data logging, the value should be 1. Is this correct? When i do paste and multiply to get to 1 ben factor the second time after i have already made adjustments, as i have said before, it changes it dramattically. Do you guys use other techniques. What about smoothing out the 3d ve table graph?

[5.7ute]

yer sorry, i understand we are tying to get a ben factor of one. So if its 7% out, do you past and multiply the 1.07 in the ve table and by doing that, when data logging, the value should be 1. Is this correct? When i do paste and multiply to get to 1 ben factor the second time after i have already made adjustments, as i have said before, it changes it dramattically. Do you guys use other techniques. What about smoothing out the 3d ve table graph?

There are a few tools around on this site to make things easier if you have excel. I can email them to you if you like, just PM me your email addy & I will send them through.
After paste & multiplying the factor, the next log should get you closer to a ben of 1.0 but there are a few variables that can still mess with your data. The main issues I have found are your intake temps & interpolation that happens in the PCM. Using a dyno the tuner can hold a steady state at say 2000 rpm 45 kpa manifold pressure. This means that the calculation is not being modified by any of the surrounding cells. If the engine was held at 1800rpm & 45kpa there would be a weighted amount removed depending on the 1600rpm 45 kpa cell value. As long as this cell was accurate there wouldnt be an issue but since we are working from estimated values, it can take a lot of logs before these incorrect cells are minimised & a balance struck between the cell values.
The IAT issue is easily solved by filtering all your data to a set IAT.

[noobtuner]

There are a few tools around on this site to make things easier if you have excel. I can email them to you if you like, just PM me your email addy & I will send them through.
After paste & multiplying the factor, the next log should get you closer to a ben of 1.0 but there are a few variables that can still mess with your data. The main issues I have found are your intake temps & interpolation that happens in the PCM. Using a dyno the tuner can hold a steady state at say 2000 rpm 45 kpa manifold pressure. This means that the calculation is not being modified by any of the surrounding cells. If the engine was held at 1800rpm & 45kpa there would be a weighted amount removed depending on the 1600rpm 45 kpa cell value. As long as this cell was accurate there wouldnt be an issue but since we are working from estimated values, it can take a lot of logs before these incorrect cells are minimised & a balance struck between the cell values.
The IAT issue is easily solved by filtering all your data to a set IAT.
i am using a dyno. The thing is though, im so close to 1.00 its not funny, im just having trouble fine tuning it.