Well, a lot of things in the definition files out there are a bit hard to find out how the 3-bar conversion happens. You can't take a 2-bar bin and convert it because I know it involves the actual table constants later on in the code, which is not defined. Now, if you have the binary files of each, you can actually just do a bit compare, and find out WHERE in the code this happens. For something like the 749 ECM, 2 to 3 bar conversions use all the same tables except for F1, F3, and F77. The actual table is different, not only the variables within. So if you go into something like Promgrammer, you can change everything, and compare the file within there to where the "compare" function says nothing is different. You do a bit compare with a hex editor, and you'll see that the files are still not the same. But later in the code (still using 749 as the example), you'll see that the MAP tables are changed to go up to 285 kPa where the stock only goes up to around 190 kPa. This is done around........0x3572......
The bit goes 1000 (8 in hex)
to 1100 (C in hex)
Here is an example (there are a few of tables that change) of what a stock 2 bar table looks like in Promgrammer for one of the spark advance tables:
Deg. vs MAP & RPM
| 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
---------------------------------------------------------------------------------------------------------------
Now the math I crunch comes out to this.......
190 kPa x .14514 = 27.4 psi
Of course, with 1 atmosphere of vacuum and one of boost, that comes out to roughly 28 psi. Makes sense.
But if you increase that MAP table to extend up to 285 kPa, which is done at around 0x3572......you can change the values of the table itself. So when you change the bits as above, it comes out as:
Deg. vs MAP & RPM
| 45 60 75 90 105 120 135 150 165 180 196 210 225 240 255 270 285
---------------------------------------------------------------------------------------------------------------
285 kPa x .14514 = 41.4 psi
You'll see that it adds roughly one more bar (atmosphere) to the readability of the tables.
Now this isn't the ONLY thing that changes. There's something else at 0x3576 that changes, but I haven't figured out what that does yet. Perhaps someone can fill in this gap.
The bit goes 1001 (9 in hex)
to 0101 (5 in hex)
I'm not sure what this translates into yet.
But that bit change registers as a 3-bar chip in Promgrammer, and other than what you can compare in Promgrammer, those are the only "hidden" values not able to be altered through Tunercat or Programmer.
But remember, this isn't the ONLY thing that changes......not even close. But it is the only two things that I can see change that aren't able to be modified by Tunercat and Promgrammer.
Hope this helps explain a little.
after the day. But it's fun figuring it out.
