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Engine speed (rpm) vs Engine Load (%)

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So I am trying to tune a base map on a Toyota Tundra (bolt-ons) using HP tuners. First thing first, I have altered the PE EQ table to target AFR of 12-13.

Now, I would like to alter the timing tables, which I thing it is the engine rpm vs engine load, found under Engine>Spark>advance using VCM Editior . . .

Here I have three tables: 1- Base 2-High octane 3- Low Octane (attached).

So based on my knowledge, I have to create a similar histogram in the VCM scanner for data logging. When I do some runs, the issue is that I only get the top raw filled in the Engine rpm vs engine load (%) histogram (attached).

Can someone let me know where I have gone wrong?Is it possible to get the histogram filled, so I can change the Spark advance tables accordingly?

Thanks in advance.

Attached Files

the number on the y axis is not the same as the engine load in the ve table, and i dont think you are data logging the engine load in the channel on the left,

you can change the learn value to make the ecu run the high octane table after every reflash or have equal values in all three timing table while tuning and then remove 3-6 degree for the low octane table

Thanks bro, I finally managed to get the data logging for Engine rpm vs Engine load (). The issue was I have used % as the raw's unit instead of () which means "Number".

So for the time being, should I replace the spark tables with the data that I have gathered (attached), or do I need to subtract this table from the main spark advance table?

Attached Files

No, the numbers you've logged into your histogram are the actual spark values being delivered. They should be close to the numbers in the high octane spark tables but there's a good chance that there may be other modified active which affect the final spark values. What you're doing is using the histogram to know where in the table you're operating so that you can make changes in the appropriate areas.

Thanks Andre. So to make things simple, I have to change the values in the spark advance high octane table. Please correct me if I am wrong. What would be my baseline here?

So looking at the two attached table, Would you be able to know where changes are doable. My goal is to optimise the tune as much as possible.

Attached Files

Please mind my basic questions as I am totally new into this domain.

Currently struggling to make a histogram of the attached table. Not too sure what parameters should I use when creating the graph.

Attached Files

Ok so the histogram tells you were in the spark tables the ECU is accessing and then you can make changes in the appropriate areas of the table. For example (I'm assuming this log is come WOT operation?), you can see you're operating between 0.80 and 1.00 load under WOT operation so this is where you want to make changes. The numbers don't align with your table values which suggests there's a modifier affecting the final timing. The fact the timing drops from 22 to 18 deg between 2400 and 2800 rpm at 0.9 load makes me suspicious some knock may have occurred that caused the ECU retard timing - check this.

Providing there isn't any knock occurring I'd try advancing the timing in the entire WOT operating area by 2 degrees and testing on the dyno to see what gives you the best torque with no knock.

In order to calibrate the MAF you want to log commanded AFR and measured AFR (from a wideband). The scanner actually creates a math channel of AFR error using these parameters and you log that into your histogram vs MAF frequency. This is demonstrated in the HP Tuners worked examples.

Thanks Andre for shedding lights on my issue. The issue now is that we are missing MAf voltage PID as the MAF table for Toyota Tundra is measure in volts unlike GM (Hz). Also we don"t have knock retard PID, instead "Knock Correct learn" and "Knock feedback" are available under channel in the Scanner. I am attaching my tune file and datalog for you guys to have a look and let me know whether I am ok or not.

Attached Files