From MAP base to MAF based...
 

So, I'm trying to learn VT. I have a few questions..

Fuel Pressure Target tables by gear...

In Tunerstudio, we use a relatively simple VE table, and adjust the number which corresponds to the LOAD and RPM at a given instance to RAISE or LOWER the AFR. This is intuitive and mechanical, and doesn't account for "targets" It just does it. For instance if I received a KNOCK at....

188kPa (13.2PSI boost pressure) around 4800 RPM I would find the cell which lists 188kPa and 4800 RPM and either examine the AFR in that instance and see if it was too much timing, or too little fuel, if too little fuel, bump up the VE cell and if it was too much timing, I would retard maybe .3 degrees in that instance. Then I would retest.

In Verstune, it does a calculation based off... gear, BAT, RPM, Load and then examines appropriate target tables and does what is necessary? So in theory, when a mod is completed I would only have to adjust my TARGETS because that is what I would ideally want to see and.... The ECU does the rest?

Are my Fuel Pressure Target tables essentially my Volumetric Efficiency table?

Is there a "getting started in VT/things to you should do to not blow up your engine" ? MS/TS/MLV has a massive following and there's almost nothing you can't search for in your specific model, category, goal. I'd like a rundown on tuning the 2.3MZR using VT if anyone has any resources.

http://i1303.photobucket.com/albums/...ps6cnk6ap7.jpg

Thanks in advance tur-bros

You will always want to be between 1600-1900psi fuel pressure at WOT, anything lower than that and something is wrong.

The fuel pressure table is not a VE table, it's not like your typical port injected car. Fueling is adjusted by scaling the MAF tables (there's 2 and they should be the same). Do a pull and be sure to log the necessary parameters (act and des AFR, MAF lb/min, MAF volts). Look at your desired fueling and compare your actual/observed fueling to it. Is it off in certain areas? If so then you need to create a multiplier based on the observed and desired number to correct the observed to be your desired. You apply that multiplier to the observed mass airflow number that is observed at that time. See what voltage the old mass airflow number corresponds to and then use that new mass airflow number and put it into your MAF curve at that correct voltage point.

That's the simple way to do it. There are other ways that are faster and less of a hassle but I'd have a hard time explaining it without visual aids. The way I do it is to create a multiplier for every point logged and corrected airflow at each point, and make a scatter plot of voltage vs corrected airflow. Use a line of best fit on the graph and take the formula it gives you from the line and apply it to the voltage values in the tune to give you the proper mass airflow numbers for those corresponding voltages. It's a fairly quick process and allows you to dial in the whole WOT portion of the curve pretty easily. Usually only takes me 1-3 revisions to get the whole curve dialed in to be spot on targets.

Fantastic explanation! Thank you!

So, I found the actual VE table, which I'm not supposed to adjust fueling by, but what are the MAF tables called in VT? The only tables which look like they're right on what needs to be adjusted after modifications are the "Fuel Pressure Target 1-6"

The MAF tables should be labeled accordingly in the sensor calibration section.

The fuel pressure tables don't need to be messed with once they're set.

So it's seriously this easy? Telling the ECU what you want, and the ECU either says, "Yup gotcha." Or "OH FUCK I CAN'T DO THIS."

Yea. For the most part. You're pretty much telling the computer when the MAF sensor has a certain amount of air flowing over it, causing it to output X voltage, that tells the computer that there is Y airflow. Assuming the sensor is calibrated properly, if the computer knows how much air is going in, then it knows how much fuel to spray in order to meet the desired AFR.