Calc.VET: correcting MAF and calculating VE (in single log)

[jorge]

Ok guys, I am following the CalcVe tuning tutorial every thing is going well but need some help understanding what is happening with the tune when the logged data is applied.

Is it fair to say?

-In the MAF table - If the logged bens are low say .97 in order to go to the ideal 1.0 Do the values in the tune need to go down in values? Also lower values equal leaner fueling.

-The MAF table is more important to be spot on than the VE table.

- In the VE table when the values go lower makes the LTFT more positive?

Just trying to get a better understanding of what is happening in the tune when the log is applied. So set me strait.

Thanks
Jorge

[WeathermanShawn]

Ok guys, I am following the CalcVe tuning tutorial every thing is going well but need some help understanding what is happening with the tune when the logged data is applied.

Is it fair to say?

-In the MAF table - If the logged bens are low say .97 in order to go to the ideal 1.0 Do the values in the tune need to go down in values? Also lower values equal leaner fueling.

Well, .97 BEN is pretty good. But for example..if you had a MAF Frequency of 5000 Hz X .97 = 4850 Hz..so the numbers go down. I am not 100% sure what the premise of your second question is. A BEN of 1.00 equates to stoich fueling. .97 BEN means the PCM has had to subtract 3% from the Injector Flow to get to stoich. Lower Bens generally mean rich, higher BENS mean leaner.

-The MAF table is more important to be spot on than the VE table.

Thats probably an accurate statement for a MAF-enabled vehicle.

- In the VE table when the values go lower makes the LTFT more positive?

If the vehicle was running solely off the VE Table. In a MAF-enabled vehicle, Trims are primarily driven by the MAF. But the lower the VE Table values, the lower the Airflow values.

Just trying to get a better understanding of what is happening in the tune when the log is applied. So set me strait.

Thanks
Jorge

Here ya go..

[WeathermanShawn]

Thought I would attach a copy of my calcpid.txt file for those that do not have GM.DYNAIRTMP.DMA in their OS. This file includes the calc.dynairtmp.pid as an alternative. Please review this and note any required changes or suggestions.

Attachment 10347

Also attached is a list of my PID selections from the scan tool when using calc.dynairtmp. Couldn't figure out how to capture the screen shot and post. Will work on that tomorrow.

Steve O

Thanks Steve:

I'll keep the calc_pids.txt on file. Sometimes different OS's have different Values, but I really appreciate the effort.

Thanks again..

[rpmauto]

Shawn,
Got to make my first log tonite. I had some issues earlier today with it. It wouldnt go into closed loop at all, and I had no o2 sensor data. I found that I switched two wires for bank 2 sensor 1 and 2 around doing my pcm swap. Anyway I got that fixed and fired her up. Took a while to get into closed loop and the trims to start, (o2 data doesnt show right in my dashboard, but does in data tab, wanted to log it just to see. It did work right last year).

At any rate most of the drive the trims averaged around -14% for the trip. I beleive I have the maps set up correctly, but in order to paste with lables on the ve table it really messes it up. I think I will start over I think I missed checking the Names box when I made the maps. I dont know what diff that makes. Take a look at the log and see what you think. (was a little hard to idle, I want the ve dialed before messing with idle)

This is the tune that is currently in the car, and what I will modify from as well

[WeathermanShawn]

Len, I think that looks like a pretty decent log.

I have your SELBENS averaging more like a -7 to -9. As I have said before, Tuning with negative Trims is a lot easier than positive.

On your VE MAP, make sure the columns.rows line up with your VE table. Here is what I came up with using a tight VE Filter..

A log like this is really only 1-2 more runs from perfection..

[rpmauto]

I am pretty sure that my columns and rows match, but it displays it like the auto ve, or what i did for calc ve last year. IE: 1.27, 1.14 ect. Yours screen shot displays it in the same units as the table. Same thing for the maf table. But with the maf you paste and multiply. (I did that and came up with a few high ones I will have to smooth.

[WeathermanShawn]

Maybe this is the issue..

NOTE: use the CALC.VE pid units that match your B0101 table, i.e. either % or g*K.kPa.

[rpmauto]

I checked that to make sure. and the table in my tune is kpa and my map is set up kpa. I will try building the map from scratch again in a little bit.

[rpmauto]

Yea, it was my map. I took for granted that it displayed in kpa, I now see that in the units it says %. Boy that makes a difference. I will get some more logs today before the storms start.

[joecar]

On the map's Data, Row, Col tabs, checkmark Show Units, sand re-save the map... this helps avoid confusion.