Originally Posted by
405HP_Z06
Great info Oz! I went through and made a few changes. Check it out:
1. DISABLE ALL TORQUE MANAGEMENT – This will eliminate all torque management within the PCM. Ignore this step if a standard transmission (M6) and continue to step 2.
A. Open the VCM Editor>Edit>Transmission>Torque Management
B. Set Abuse Mode Enable = False
C. Set Abuse Mode RPM, Abuse Mode TPS and Abuse Mode Speed = 0
D. Select>Abuse Mode Torque Reduction vs. RPM. Set all values = 0
2. LTFT TUNING –
A. In the VCM Editor>Edit>Engine Diagnostics>General>MAF Sensor Fail Frequency = 0. This will set a P0103 code and turn on the SES light. Don’t worry about the light at this time.
B. In the VCM Editor>Edit>Engine>Spark Advance>Main Spark vs. Airflow vs. RPM Open Throttle/Moving. Copy the High Octane table to the Low Octane table. The computer reverts to the low octane table when MAF is unplugged, this will assure optimal timing.
C. Start the VCM scanner>Histogram display. File>Connect then Tools>VCM Controls>Fuel & Spark>Fuel Trim Learn>Reset Fuel Trims.
D. Changes to the LTFT’s do not take effect immediately – the PCM requires at least 50 minutes or roughly 100 miles to allow for the PCM to relearn it's fuel curve. Try not to enter PE mode while driving and logging for this procedure. Stop logging and save the log. Do NOT turn off the engine until the log is saved or it will be lost. Go to VCM Scanner>Histogram display>LTFT's. Open the VCM Editor>Edit>Engine>Airflow>Main VE and select Primary VE vs. RPM vs. MAP.
E. The goal is to get ALL LTFT’s between 0 and -4. Positive LTFT's indicate fuel is being added because of a lean condition. Richen this cell by increasing the VE table value by the amount of the LTFT value. The operation is opposite for negative LTFT's.
If LTFT = (4), VE cell value is 67, result would be (67)+(4)=71 - increasing the VE, which is adding fuel. If the LTFT was (-4), the result would be (67)+(-4)=63, decreasing VE and thus reducing fuel. To decrease LTFT values, a smaller number or number closer to zero, ADD the difference between the positive LTFT value and zero to the corresponding cell in the VCM Editor>Edit>Engine>Airflow>Main VE>Primary VE vs. RPM vs. MAP table. To increase a LTFT value, a larger number or number farther away from zero, SUBTRACT the difference between the LTFT value and zero and SUBTRACT from the corresponding cell in the VCM Editor>Edit>Engine>Airflow>Main VE>Primary VE vs. RPM vs. MAP table. For example, In the VCM Scanner>Histogram display, the (.8, 40) cell, 800 RPM's and 40 kPa, is 4. To bring the VCM Scanner>Histogram display>LTFT cell (.8, 4.0) DOWN to 0 from 4 ADD 4 to the (.8, 4.0) cell in the VCM Editor>Edit>Engine>Airflow>Main VE>Primary VE vs. RPM vs. MAP table. If the VCM Scanner>Histogram display>LTFT cell (2.0, 30) is -10, SUBTRACT 10 from the (2000, 30) cell in the VCM Editor>Edit>Engine>Airflow>Main VE>Primary VE vs. RPM vs. MAP table to bring it UP to 0. This will not work out exactly but will be VERY CLOSE.
F. Repeat steps D-F until ALL values in the VCM Scanner>Histogram display>LTFT are between 0 and -4. Try to complete this on the same day for best results as LTFT values can vary +-4% per day.
G. Once all values are between 0 and -4, look at the VCM Editor>Edit>Engine>Airflow>Main VE>Primary VE vs. RPM vs. MAP>3D Surface graph. If the 3D Surface graph looks choppy, click on polynomial smoothing ONCE. This will smooth out the table values and provide a more crisp throttle response. Now rescan, and do step E.
3. WOT PE TUNING – Do this only AFTER all LTFT's are BELOW 0. This method uses the stock narrow band oxygen sensors which are not that accurate for this area of tuning.
A. Open the VCM scanner, do not worry about resetting the fuel trims they should be learned at this point. If not, it takes roughly 100+ miles or 50+ minutes of driving to set the LTFT's.
B. Open the VCM Scanner>Histogram display and do a nice 0-70 or preferable 0-100mph run. Look at knock retard FIRST. If knock retard is present, skip to next section then come back here. If no knock retard is present, continue to the next step.
C. Again, if NO knock retard is present look in the VCM Scanner>Histogram display>Air/Fuel tab at the 100(kPa) row. It is best to log AFR with a wide band sensor to correlate the stock narrow band oxygen sensors mv’s to actual AFR. Most cars seem to like narrow band oxygen sensor reading between 890mv - 900mv.
D. For example, at 100(kPa), 3200(RPM) the narrow band oxygen sensors are at 950mv. We want to bring that down to 890mv. I do not yet know exact equation, but go to the VCM Editor Engine>Fuel>Power Enrich, PE Enrichment>V8 Mult vs. RPM. Make sure Plus and Selected are bubbled in. In this case the narrow band oxygen sensor is reading rich, so bring it down by SUBTRACTING .01. NOTICE THE DECIMAL!!!! VERY IMPORTANT!!! If lean, BELOW 890mv then ADD .01 at a time. This is a small increment but we do not want to hurt the motor.
E. After making the changes, go back to step B and repeat until the oxygen sensors are in the appropriate range.
4. ELIMINATING KNOCK RETARD -
A. In the VCM Scanner>Histogram display>Retard, look for ANY knock retard. For example, cell (4.0, .20) shows 4 degrees of knock retard. This should be 0, so SUBTRACT 4 from the VCM Editor>Edit>Engine>Spark Advance>Main Spark vs. Airflow vs. RPM Open Throttle/Moving>High Octane (4000, .20) cell. Values cannot be less than zero in this table.
B. In the VCM Editor>Edit>Engine>Spark Advance>Main Spark vs. Airflow vs. RPM Open Throttle/Moving>High Octane, go to the (4000, .20) cell AND/OR whatever other cells that have knock retard and SUBTRACT the amount of knock retard that is present in the Histogram display from the value that is in the corresponding cell in the VCM Editor>Edit>Engine>Spark Advance>Main Spark vs. Airflow vs. RPM Open Throttle/Moving>High Octane table. Subtract by simply clicking on the Plus selection and in the box type -4 or whatever number you have to subtract by and click commit.
C. Run a new scan and verify NO knock retard is present. If still present, repeat from step A.
5. A4 TRANSMISSION SETTINGS -
A. Ensure all Torque Management is disabled. If not, see Section 1.
B. Open the VCM Editor>Edit>Transmission>A4 Shift Speed. Set WOT Shift Enable %TPS = 90.
C. Set WOT Shift Disable %TPS = WOT Shift Enable %TPS-10 or 80 if you used the parameter in step B.
D. Look at VCM Editor>Edit>Transmission>WOT Shift RPM vs. Shift. Set these table parameters to the desired WOT shift RPM for each gear. Keep in mind there is a slight delay at the shift point that will cause the engine to exceed these RPM settings. Ensure the VCM Editor>Edit>Engine>Fuel Control>Fuel Cutoff, DFCO>RPM Limits>P/N Cutoff RPM is roughly 500 RPM higher than these settings. We don’t want to hit the rev limiter during the WOT shift. Set Normal, Performance, and Hot tables to the same parameters.
E. VCM Editor>Edit>Transmission>WOT Shift Speed vs. Shift--PLEASE PROVIDE ME WITH A GOOD LINK FOR THIS. I KNOW THERE ARE TABLES/CALCULATORS PER GEAR OUT THERE.
F. VCM Editor>Edit>Transmission>Shift Speed vs. %TPS vs. Shift = Leave stock parameters.
G. Go to VCM Editor>Edit>Transmission>A4 Shift Properties>Desired Shift Time vs. Torque>Normal. I basically guessed here, and could use some input. For the first half of
the torque band, I set shift time to .500 so you get nice soft, smooth shifts. Starting about midway, I decreased to .250 and for last 1/4 I changed to .100. I heard you do not want to go below .100 or else you will run into some kind of gear crossing? Please feel free to fill in here.
H. Go to VCM Editor>Edit>Transmission>Base Shift Pressure vs. Torque vs. Gear. Okay this is kind of weird and I don't understand it, but what I PERSONALLY did was again take half of the chart and to the left. Take this and set to a LOW # like 10. I have a shift kit in my car, and setting first half gives me nice smooth shifts. You would never know I had a shift kit or torque converter in my car. I then took the middle and started beefing up shifts in increments of 10 then increments of 15. By far right of table I have shift pressure up to 96. Now, when you drive my car at 0-1/4 throttle it is SMOOTH. 1/2 throttle, you can feel a nice crisp shift. WOT it chirps tires from 1-2 and 2-3 shifts nice and hard.
I. Upshift/Downshift pressure modifiers - I don't understand. If you do, teach me and I'll update.
J. If you have a shift kit, leave max line pressure at 90. If not you can probably set to 100.
Edit: Updated VE tuning operation
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Modds-SLP lid-flow master cat back-ported MAF.
), you also need to go into Engine, fuel control, cot/lean cruise and disable lean cruise as it is active from the factory. if you dont do this it reverts to open loop mode above 76km/h so you are unable to record LTFT above that speed for tuning. Just set the enable speed to 276km/h.
This has helped a bunch, but just have a couple of ?
lol
This will be my first post. 
I know if I continue to read the posts contained on the HP forums that I would probably find the answers to the questions I will ask. I have read many of the posts in different areas of this site and my eyes are getting tired. I have many questions but will only ask a few. We do engine conversions into Land Cruisers and Jeeps. All of them will be 4.8, 5.3 and 6.0. Possibly an 8.1 at times. 