BTW, the tutorial has it inverted: COL=MAFFREQ, ROW=ValueQuote:
Originally Posted by mr.prick
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BTW, the tutorial has it inverted: COL=MAFFREQ, ROW=ValueQuote:
Originally Posted by mr.prick
I screwed up. :doh:
it should be:
ROW={GM.MAFFREQ}
COL=Value
If only paste and multiply won't work then there is something wrong with the map labels.
Post your map.
Pasting with labels is good for specifically selected cells,
if you copy the whole map and paste over the whole table that works as well.
Paste with labels is best IMO.
RevGTO, can you post some screenshots of your scantool map and your tunetool B5001 table.
[ display the map or table, do Ctrl-PrtScrn on your keyboard, then paste this into a Microsoft Paint file... then Reply to this thread, click Go Adavnced and then Manage Attachments. ]
When you created the map in the scantool, did you do these steps:
- in tunetool, copy-with-labels of B5001,
- in scantool, for each or row and column properties, Paste (without copying anything else in between).
The scantool map's axis's must look exactly like the B5001 axis's (including decimal digits).
Ok, guys, Here is the LTFTBEN table. After messing with trimming the image down in Paint, and saving it as a jpg, I finally got it to upload.
Here are the B5001 files; #1 is the file before the paste/multiply of the LTFTBEN results; #2 is after.
Just eyeballing the table, it looks fine.
If you have a calculator, or can do math in your head..just check a few frequencies vs LTFTBENS..I.E. 4000 Hz X LTFTBEN = New Value, etc..
Its the only Table where you have to paste and multiply (with labels). I could probably figure out a way to eliminate that step..but it seemed more work to do that, than to just putting the new values back into the tune.
Then if you do another CALC.VE Table log..the precision and accuracy just gets better, as your MAF Freq (g/s) vs LTFTBENS becomes even more accurate.
Overall, how were your results?
RevGTO,
On the scantool map, does the second column say "Value" at the top (in post #126)...?
If it doesn't then paste-with-labels won't work.
[ it probably says "RPM"... in the map properties, on the Col tab, change the Title to "Value". ]
http://forum.efilive.com/attachment....5&d=1269203449
This map does not have matching labels, this is why you can't paste w/labels.
I have worked out the equations from first principles to gain an understanding of the big constants (and their units)...
The equations I came up with are in the attached calc_pid.txt.
Original equations: we don't really know where they came from, Paul doesn't have that info anymore...
New equations: I understand the equations, constants and unit analysis.
The differences between the new ones and the original ones:
- VE[%]: the new one is about 1% less than the original.
- VE[VE]: the new one is about 18% less than the original (and matches my existing B0101).
note: [VE] units is a shorthand for [g*K/kPa].
So, try the tutorial with the new equations and see how you go.
Use VE[%] if your B0101 table is in %.
Use VE[VE] if your B0101 table is in g*K/kPa.
:)
See here for derivation:
showpost.php?p=117044&postcount=103
showpost.php?p=117048&postcount=104
Joecar is being very humble when he said he 'worked out the equations'.
His actual work would probably take up half a page. He made something very difficult easy (at least to me). Thanks for the mathematical insight! It makes me wonder if VE Tables were really all done on a dyno, or mathematically solved in a similar manner...
Thanks..:cheers:
I thought "matching values" meant that the LTFTBEN table had to have the same row numeration as B5001 - which it does. Do you mean to say that since the data begins on the 8th row, that copy with labels won't carry over the first 7 blank rows - and so the table is misaligned, and doesn't have "matching values"?Quote:
Originally Posted by mr.prick
And here's a shot of the column set up, as that has been questioned ...
RevGTO, the column heading should say "Value" with an uppercase "V", same as table B5001 (your pic shows "value").
Shawn, thanks for the kind words... :cheers:
I hope I did learn something 30 years ago and not just warm the bench at school... :doh2:
My math is maybe not so good, which would explain the difference :doh2:Quote:
Originally Posted by joecar
Paul
Ok, thanks. It's shown in lower case in the Tutorial, so if that's erroneous, correction needed there.Quote:
Originally Posted by joecar
Thanks. Noted. The tutorial will be updated.Quote:
Originally Posted by RevGTO
Thanks everybody for the feedback.
I will try to post up a list of Tutorial Typos, updates, etc..
It is always smarter to get them all corrected in one big update, but we realize people are using the Tutorial in its current form.
Other than the necessary 'computer work', has this method of tuning made tuning easier or simpler? Any feedback on the actual tuning method itself?
Thanks..
Once you setup the maps it's pretty simple, one log gives pretty good results (with filtered out throttle transients, as said in the tutorial).
Explains why I couldnt multiply with labels. Thanks. I'll try the new formula in the next two days.Quote:
Originally Posted by joecar
So far these are the Typographical errors noted with the Tutorial, or where clarification is needed.
If anybody notes any others, please post them up.
Thanks..
***Tuning Tutorial Changes:***
Page 2: Update calc_pids.txt
Provide Link to Text Thread?
Page 6: Line 10. Last word value, should read Value.
Page 7: Change Filter to Read SAE.ECT.C less than or equal to 80C
Yes please, if anyone has found anything that needs fixing, please post.
Update: I did a base run, adjusted my VE & MAF tables, and then did a number of logs with the altered tune. My results so far show a fair amount of variability between the logs. For example LTFTBENs vary from the 1.00xxx range to the 0.97xxx range for the same hz category from log to log.
I had been using a downloaded VE table from Holdencrazy from a car with very similar mods. The VE results have been consistent enough for me to have established my own baseline B0101, with generally lower VE% numbers than downloaded table I was running.
Fuel trims have stayed close to what they were in my previous tune, but vary some from log to log. One was nearly ideal in the the -3 to +0.8 range, with the exception of numbers as high as +4 at 0%TPS in decel. My car has always tended to trim upon decel for some reason. I should say that my previous tune was developed when I ran OLMAF for a year; I continually adjusted my MAF calibration to get my actual fueling in line with commanded. Thus my MAF/VE combo was fairly close resulting in decent fuel trims even before factoring in the CALC VE results.
I'm going to take some more logs with my freshly edited Main VE table. If those results continue to fall within range, then another LTFTBEN adjustment should get it squared away.
My only issue is PE. My results so far indicate it is off. But it is hard to do extended runs at WOT on local streets and highways. I'm not going to be able to get a good indicator there until we have some decent weekend weather and I get the car to the strip.
RevGTO:
Thanks for the report.
It was very informative. Believe it or not that swing in LTFTBEN's is not that uncommon. Weather changes, fuel type, even your fuel level can sometimes alter the Trims.
But, it is important to get consistency. And it sounds like you have. Your right, probably by run 3 you can be dialed in.
Trims on Decel. Always an interesting topic. So many of these Trims get locked in early on the learning curve. Just depends on your year of vehicle and what Fuel Trim Cell (FTC) you are in. Sometimes Decel gets it own unique FTC, and once its hard to budge some of the Trims in those cells.
More worrisome is PE. This method relies on the narrowbands and its relationship with LTFTBENS. Obviously PE ignores the narrowband feedback and requires a little more finesse to get it right. Suffice to say, if you can enter PE Mode with 0+ Trims, then you just need to look at the % difference between Commanded and Actual AFR (BENS) and adjust the MAF Freq accordingly.
Perhaps at some point the Tutorial can link to 'Methods of WOT Turing'..as it does require a some different approach. The challenge in writing a Tutorial was not only where to begin, but where to stop. Hopefully in the future we can figure out a way to combine Idle and WOT Tuning into a series of Tutorials.
Thanks for the feedback. Hope you can get your WOT Tuning done. Its only 10% of the VE Table, but arguably the 10% that is the most fun :grin:!
We've got two documented trials now. Lets keep them coming guys! I'll get more data next Tuesday or Wednesday.
You're so right. I took one of my logs after putting some gas in the car, and the results went wildly off ... LTFT's in the -12-13 range. MAF readings too. I dropped that log when I factored in my results.Quote:
Originally Posted by WeathermanShawn
One thing that I've learned from this approach to tuning is that there is a certain statistical margin of error in logging that cannot be overcome. That probably has to do with the fact that all the factors in the system cannot not fully accounted for.
As a result of this tuning approach, my VE table is undoubtedly closer than it's ever been. I've given my MAF tables another round of adjustments from LTFTBEN multipliers ... we'll see where that gets me when I log tomorrow. If my fuel trims are still overactive, then I know I can manually bump my MAF settings to where my LTFT's are close to ideal.
Thanks RevGTO:
Looks like you and at several others have had been reasonably successful in following the Tutorial. We will 'polish' up some of the typo's and update the calc_pids.txt information shortly.
I think it was very perceptive of you to see the normal variances in tuning, and to know when you are within the tuning 'zone'. It is a good idea to manually tweak when logging and tuning has taken you as far as you can go.
Thanks to you and to the others who have helped..:cheers:
After filling up your gas tank, the cold fuel will throw LTFTs off for awhile.
Wait until LTFTs settle down before making changes otherwise
any adjustments made will be exaggerated and need to be undone later.
LTFTs get highly negative after I fill up the tank.
Need some help. I finally got the Calc VE table to work, however the displayed values in the map are wacked out (way too high). I looked at the pid display in the scan tool and noticed it wouldn't let me select % or VE and the displayed values in the Units column are g*k/kPa,%. Can someone take a look at the attached txt file and see what's wrong? TIA
I noticed that was your sae_generic.txt file.
I think you want it as your calc_pids.txt file. Look under 'Tuning' after you add it (My documents..user configuration..).
I have attached Joecar's latest calc_pid.txt file..Just make sure the displacement takes..You may have to enter the amount in Liters..per the Tutorial..
Just make sure you have DYNAIRTMP & LTFTBENS, MAF (g/s)selected also.
That should do it..
DrkPhx,
Try the attached sae_generic.txt file (it has your 6.587L displacement)...
Be sure to use CALC.VE_Table a rather than CALC.VE.
Thanks Joecar. I see the option to select the different units now, but I'm still getting wacked out values in the scantool map.
For the "VE" map there are values between 1.21-1.47 in the lower rows. When the same values are displayed in % they range between 44-62%. Maybe I'm missing something; but that's a huge difference.
Hey DrkPhx:
Probably need to see that log if you have time.
Generally (depending on displacement) a '100'% VE' equates to ~ 2.49 g*k/kPa. Of course that depends on DYNAIRTMP, air density, etc..
It is confusing. There is a CALC.VE and a CALC.VE Table. And you have to make sure displacement is being properly calculated.
If it makes you feel any better..once you get it..it is never hard again!
If you have successfully logged all the PIDS, Joecar or I can double-check your CALC.VE Table %'s on this end.
I'm definitely logging the Calc.VE_Table pid. I don't have the Calc.VE pid selected.
I just looked at my pids and didn't even realize GM.DYNAIRTMP.DMA is coming up invalid and not logging. I have it set to C.
That's what's causing the VE values to be wrong...Quote:
Originally Posted by DrkPhx
Which year/model and OS id do you have... (the latest V7.5 software has an update for '97/'98 OS 19980200)... Edit: I am mistaken, I confused this with something else, sorry.
if your OS doesn't have DYNAIRTMP_DMA, then you can approximate it using 0.85*ECT+0.15*IAT or by looking up the temperature blend table.
Joe, what's the basis for this estimator?Quote:
Originally Posted by joecar
It's 98 OS 19980100.Quote:
Originally Posted by joecar
How close is that formula to the pid? Can someone do a quick comparison between the two and see how close the net values are?Quote:
if your OS doesn't have DYNAIRTMP_DMA, then you can approximate it using 0.85*ECT+0.15*IAT or by looking up the temperature blend table
Where did you find that ? I just checked OS 19980400 (that's the one I asked for) and a quick check of OS 19980200 and they are both X out as not valid. Is there something else I need to look at? Do I need to re-validate PIDs?Quote:
Originally Posted by joecar
Thanks.
Hey Guys & Gals:
Its possible Joe may have went to church or slept in. I am sure he can explain the 'estimator'. It merely an attempt to approximate the 'charge temperature blending' (B4901)..though it varies a lot by OS and year.
The Look-Up Table 'works', but has a problem with Low Airflow (< 10 g/s) in interpolating.
The difference between CALC.VE Table (with DYNAIRTMP) and the the older CALC.VE (No DYNAIRTMP) is ~ 3-9 %. CALC.VE Table will be greater and is highly advised to use (and also very accurate..I.E. MAF Failure verified..) I am sure Joecar can track down the status of the DYNAIRTMP PID..
Attachments Follow..
Sometimes PIDs are invalid until you start logging or monitoring.Quote:
Originally Posted by Ninety8C5
Select them anyways and start logging/monitoring to see if they become valid.
Of course calc_pids need their dependent PIDs selected to be available.
Quote:
Originally Posted by joecar
Quote:
Originally Posted by redhardsupra
It was late last night when I typed that... :doh2::doh2::doh2::doh2: <- me slapping upside my head 4xQuote:
Originally Posted by DrkPhx
Sorry, I had meant to type this: 0.85*IAT+0.15*ECT
i.e. it should biased toward IAT.
I intended that as a simple estimation, exactly what Shawn guessed I was doing...
I say this from looking at B4901 and from observing DYNAIRTMP_DMA say when VSS > 30 mph in various logs...
I should have instead said to study B4901 for your airflow range, which brings us to the next point:
A more accurate way to do this is to do a lookup of the B4901 values as suggested by mr.prick earlier in this thread...
and this is exactly what Ninety8C5 did: showpost.php?p=118165&postcount=29
[ but this still doesn't factor in B4902 ]
:)