Help with number in code

**myburb** · 11-12-2015

I am using 6395 modified BHDF OE. I have a disassembly of BJKZ which I think is really similar to my bin. I have to add here I know nothing about code,binary or ???. On line 4AF2 there is a calculation
TBL = DEG C + 40

i would like to manipulate the 40 to a number of my choice. My first tries would be 45 and 50.
Is there any way an ordinary guy can do that?

**1project2many** · 11-12-2015

Hmmm...

That math is often built into the coding in such a way as it's not a changeable function. The ecm doesn't "decode" those numbers which is why we have to.

Line 0xE363 begins a set of steps which uses the table you're looking at. It references the current airflow value then gets a MAT multiplier from a table at 0x4AE1. At 0xE36C the coolant is referenced, then a test is made to see if MAT is less than CTS. If MAT is greater than CTS then MAT is used alone, but if MAT is lower than CTS then a value is calculated based on airflow and the difference between MAT and CTS which is added to MAT. The result, either MAT or MAT plus added value, is then used to look up a value in the 0x4AF2 table. The value obtained from 4AF2 is divided by two then added to a hard coded value of 29,824 and saved. In this disassembly the 0x4AF2 table is all zeroes so the result of this lookup is always the same: 29,824. Is your calibration also showing zeroes in this table?

**myburb** · 11-12-2015

Thanks a big bunch for the info and the location info. As I said I am using disassembly info from what I think is a similar bin but not my actual. At position 4AF2 my table shows the numbers that are the result of mat +40. That is what I would like to manipulate. In tunerpro there is no table input. Position 4AE1 is a ratio table that can be manipulated in tuner pro. That table in the stock bin is filled with zero's. In my case I have enabled the mat sensor and have experimented with different ratios. I currently have the boxes filled with .9 with the sensor in the air cleaner base. I am pulling air from under hood for the winter as I have an aluminum intake and don't run hot water thru so concerned about icing. Everything is working great and as the air cleaner temp changes the correction keeps the afr constant. The only problem is with a constant of 40 the afr is pulled down by about .2 across the board and I am guessing a number of 43-45 would correct that. Also think that number would possibly need to be manipulated more when summer cold air intake was put back on. But if it can't be changed it can't so will work around it. Thanks again.

**1project2many** · 11-13-2015

The only problem is with a constant of 40 the afr is pulled down by about .2 across the board

That's not how it works. That 40 just tells us, the humans, how to relate that number to temperatures we know. It doesn't affect the computer at all. Want to change it to 45? Simple... invent your own temp scale, "myburb degrees = table value -45." Then you can write out new temp values based on what's in the table. But the ecm doesn't care because the ecm doesn't use Celsius or myburb degrees.

In tunerpro there is no table input.

Ok, so you're saying that table is not available to edit? That's different. Which definition are you using? It's not too difficult to add a table. I can try to do a quick walk through later tonight if you post the def, or lmk if it's a definition that's hosted here. After the table is added you'll be able to adjust the temp values in the table up or down. You could bias the table either way. But really, from the code I'm seeing it looks like you can do the same thing by changing what you've got in the 4AF2 table.

**brian617** · 11-13-2015

Here is an $OE XDF with the hidden MAT tables added.

**myburb** · 11-13-2015

My xdf is advanced $OE TP5 v250 and the table input for 4AF2 is called "inverse air density @sea level vs blended intake temp" and I was looking for things with mat in the parameter. In the xdf that Brian referenced the 4AF2 table is called "mat vs intermediate mat or vs coolant". That was going to be my next table to fool with. I will burn some experimental chips and stick them in on test days.

**1project2many** · 11-13-2015

I apologize for not getting back to this last night. I think yesterday's lunch wasn't fully cooked as I was in pretty rough shape when I got home.

Thanks, Brian, for posting that definition.

myburb, you've discovered how to search for parameters and tables by their location, then? It's how I usually look for a parameter. I'm not real familiar with TP though so I can't advise how to do it without having the software open.

Oh, and some clarification for my last post: I said

it looks like you can do the same thing by changing what you've got in the 4AF2 table.

I mis-identified the table. I should have said the 4EA1 table can provide the same results. That would be my preferred table to make the changes you're looking for. The multiplier in those tables should have an upper limit of 2.0.

Keep us updated.

**brian617** · 11-13-2015

Originally Posted by myburb

My xdf is advanced $OE TP5 v250 and the table input for 4AF2 is called "inverse air density @sea level vs blended intake temp" and I was looking for things with mat in the parameter. In the xdf that Brian referenced the 4AF2 table is called "mat vs intermediate mat or vs coolant". That was going to be my next table to fool with. I will burn some experimental chips and stick them in on test days.

I renamed the tables to match the BJDR hack, and to help find them via the search function.

**myburb** · 11-13-2015

The 4AE1 position is where I have been experimenting and the 4AE2 also looks like it could be used for fine tuning, just getting there in a different way. I have another query on the same lines. On two different dissassemblies location 4AE2 appears to be a representation of mat plus a constant of 40. That would be a temp BEFORE blend. When you look in parameters of the bin of in TP the location 4AE2 appear to be a representation of temp AFTER blend. I am having trouble wrapping my head around how there can be two different representations at the same location.

**myburb** · 11-13-2015

I forgot to include the results of my testing of location 4AE1. With the mat sensor enabled a selection of 0 gave full temp control to mat, a selection of 1 gave full control to CLT. In the carb world roughly 20 degrees went one holley jet size and I tried to copy that and I came up with .9 at 4AE1. That still needs fine tuning

**myburb** · 11-15-2015

After 10 chips and $50 fuel the burb is running awesome on mat. I have to say thanks to 1 2many for the tree of processes that he added a few days ago. It really helped me follow how things went. The key is the inverse density table matched to YOUR standard day temps/ve.