what's this pit stop in excel. ?? :Eyecrazy:
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what's this pit stop in excel. ?? :Eyecrazy:
I set up a spread sheet so that I could apply a percentage of the correction and not the whole correction. Shoot me an email to SAJ79 at aol dot com and I'll send you the sheet if you want. It might be a few days til I get to it though...it's on the other computer.
I am using earlier logs, and just dabbling (stuck offshore)...
Thanks to TAQuickness for showing me the trick of being able to add calc PIDS if you happened to log the parameters needed for it AFTER the FACT :)
OK, does this look right?
http://www.retrorelics.net/jim/Board...MAFFreqben.jpg
So I would do something like this to modify the MAF FREQ table when I have enough samples...This is halfing the Ben Difference per SSpdDmon
http://www.retrorelics.net/jim/Board...xcelMAFben.jpg
I would apply the new values and relog til I was satisfied...
Beer,
There are three things you may encounter:
* The MAP col label 8000 will prevent you from direct copy with labels. Using "Value" instead allows paste with labels.
* There is currently a 64 row limit for MAPs which is an issue for 12k MAFs
* My experience has been that adding the MAF back into an optimized VE MAFless tune tends to lean out AFRs.
Let us know how it works out?
One other thing to be careful about...
Make sure you have enough resolution on your log. 7.2 and 7.24389 are two totally different numbers when it comes to the MAF. Other than that, it looks like you're on the right track. :)
No matter the precision you see the software always copies out to 6 or so decimal places. This can be verified by copying and pastign in Excel
Top get the required 85 rows, you have to use the Create Labels button, and specify start 1500, stop 12000, step 125.Quote:
Originally Posted by Bruce Melton
Quote:
Originally Posted by joecar
And everytime you edit that map you will have to re-create the rows
Thanks for the additional info guys, I get paroled Thursday, have a short two weeks home, and the driving season is drawing to a close in New England. I got 42's # injectors to put in and I am gonna play with the VE tune then roll into this MAF tuning (need the MAF for dry Nitrous).
With any luck I will have that done and get the opportunity to see what the tuning did N/A on the dyno and then get some dry nitrous dyno's/logging above the 50 shot I was limited to before I put the car up for the season.
Thanks for the help will post my results :cheers:
Could someone host that .map file? Those attachment links don't work.
...when I try and download it, I end up downloading attachment.php.
Try right clicking and rename the file " maf_error_206.map ".
You should then be able to import it.
Regards,
Neil.
SSpdDmon, Do you still have that spreadsheet for the MAF % correction avaliable?
Ok, this is probably a dumb question, but here goes. When you disable the LTFT's and STFT's, does this eliminate the O2 sensors? Will I have to have a separate bung in the exhaust for my LM1 sensor to do the MAF calibration? Thanks!
MO - disabling the trims is not necessarily the same as eliminating the NB's. By disabling trims, you are no-longer adjusting fuel from the NB feed back. A few more steps would be required to eliminate the NB's all together.
But, once the trims are disabled, you can physically remove the NB's and install WB's for tuning. If desired, you could go a step further and use one of your WB outputs to simulate the NB's as well.
So, once you disable the NB, you just pull it out and leave it plugged in to the harness while you use the bung for the WB? Thanks.
I wouldn't leave it plugged in. In fact, all 4 of mine have been sitting in a box in my garage for close to 2 years now.
Careful TA, he his "up North" where every day is not the same.
If I understand correctly, I need to do the following to accomplish the MAF tuning.
1. Disable the LTFT's and STFT's
2. Remove a NB to place the WB in it's place.
3. Disable the DTC (MIL) for the NB, so it can be unplugged.
4. Drive and log the MAF ben that is in this thread, like the Auto VE tuning.
5. Paste the correction factor into the MAF table.
6. Drive, Log, paste again. Repeat this step until satisfied.
7. Re-install NB, turn fuel trims back on.
Is this basically the process? I am trying to avoid having to install a separate bung for the WB. Thanks.
that's it in a nut shell.
Bruce - I hear ya. Winter time here is rather dynamic. One day we have a high of 80, the next 50.
Yes...pm me your email and I'll shoot it over to you.Quote:
Originally Posted by heavyfoot
OK that was interesting:Eyecrazy:
I made the mistake of trying to MAF calibrate using CL and I guess the trims were messing me up. Seems like I was chasing them and getting nowhere, the bens were 1.04-1.05 I would make apply the ben to the MAF table and I chased (again they were 1.04-1.05) them til I threw the Fuel Trim Rich codes, then I came back and reread the thread.
So I did a couple of logs yesterday OL with MAF enabled (using the stock MAF table) what I was expecting to see was Bens of 1.00 or so since thats where OL (no MAF) had them and what I ended up with was Bens that were .85 on the MAF Freq MAP. I averaged the readings from the two logs, and applied the .8X bens (copy w labels, paste and multiply w labels) to the MAF table. Seems like the MAF has a huge part in CL (I thought it was used 4000 RPM and higher).
I am hoping that my MAF Bens start doing what I think the should and be closer to 1.00
Am I on the right track now?
You can tune the MAF in open or closed loop. Closed loop, you use the trims assuming your NBO2's are somewhat accurate around stoich. But, you are limited to CL operation for tuning accuracy. Outside of CL, I don't trust the NBO2's at all. The trick is to disable LTFTs and tune off of the averages of the STFT percentages. Filter out fuel trim cells above 19 to get rid of open loop/decel, fuel trims where STFT's=0 (-0.01%<STFT's<0.01%) to get rid of laziness, and cells where TP% is changing too much. This will at least get you close.
If you want to tune with the WBO2 and BEN's, then you need to command open loop, log the appropriate pids, and again use the right filters.
Either way will work assuming two things...
1) You're doing it right...no user error.
2) Everything mechanical is working right....WBO2 or NBO2's, no intake/exhaust leaks, etc.
If your car suffers from the side effects seen on many C5's with LT headers, tuning the MAF in CL might become troublesome and cause you to chase your tail a little. If not, I'd say the tail chasing you were doing is more related to user error (maybe you didn't use your filters right?).
Using the VE filters in the tutorial, but I am accepting less than 50 hits (I think 10) because my test circuit is limited in what I can do traffic and time wise (limited laptop battery life). No headers, pretty much stock, have a new LS6 intake vice the LS1 and catbacks. Using an LC-1 WB for logging.
What I did for those is look at what the surrounding cells are doing. Data points with 10 hits are useless. The stock MAF curve is fairly accurate and does well when progressively scaled. If you use the compare feature to look at your current calibrations vs. the stock table, you can see the delta %. If 3000Hz is roughly 3% over stock and 3500Hz is 3.5% over stock but you don't have that many readings for the 3125~3375Hz range inbetween....increasing them 3.25% over stock is a relatively good educated guess and will get you close. If you use the spreadsheet I built, it's easier to see the percentage change and make adjustments for the cells you didn't quite hit enough times. Ironic I push the spreadsheet given the title of this thread??? Yes...but it's extremely easy to use and it's virtually dummy proof.Quote:
Originally Posted by Beer99C5
My MAF table increases at .5% intervals over stock starting at 3000Hz until it reaches 6.5% over stock at 4500Hz (ie 3000 has a .5% increase, 3125 has a 1% increase, 3250 has a 1.5% increase, and so on until I get to 6.5% at 4500). Above 4500Hz, I carry the 6.5% increase all the way to the top because that's what I know the car likes at WOT. I used these settings based on watching the trims and using the WBO2 for WOT. Now my fuel trims fall into a -5%~-2% range. It's not 100% perfect nor will it ever be....but they're in a good spot. That, IMO, is the trick to tuning. If you drive yourself nuts sweating the details trying to get everything in line 110%, you'll never be able to enjoy the vehicle. In my case, the -5% LTFT's are well within the limits of the PCM for adjust during CL operation and WOT is right where I want it...so, I'm done with this tune until the next mod. :)