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I was asked in PM some questions on getting started. I am posting it so others can see it and ask questions. Myself and others will try to make this as useful as possible so it can go on the site itself. If you see anything incorrect or that you do different, please post.
Depending on your application/mods, your starting point will vary. If you change the injectors or fuel pressure, your first goal is to go to the Tables > Fuel > BPW vs Desired EGR. This is your fuel constant. There is math involved, but I hate math:P If you turn off the EGR, this is a simple 1 setting change, at the 0 position for no EGR. Raising the number = smaller injectors. Im used to doing this with the real number, not the actual converted number GMPCM gives you. Anyway, you change this until the car is tunable basically. If you set it till your idle is decent (not dead on persay, it could be rich or lean, but as long as its in the idle range you are fine).
After the constant is set, the next goal is to tune idle. You have to watch the BLM and INT values. BLM is long term fuel, INT is short term. At idle, this is easy to watch as your INT will move first, and as it sits above or below 128, the BLM will slowly start moving in the same direction as the INT. Eventually, unless the fueling is out of bounds of the programmed range (you can set min and max values for int and blm), the INT will sit at 127-129 and the BLM will stay. If the BLM is over 128, you need to add some fuel. If its under, you cut fuel. Supposedly you can take the percentage it is off from 128, and multiply your VE section by that to get the total. To do this, you have to add up the base VE (F30 table under fuel) with the 3D VE table (F29). I don't bother with the math as ive done it long enough to get a feel for how much fuel to change in the tables. For idle though, you will want to change the F29E table, or idle VE table. Again, if its out of range (can't go under 0), you can either change the fuel constant again, or go the base VE table and raise the numbers there. It does use the 400-800 table there as well in the idle fuel calculation.
After that, its cruising fuel, which is where you need to datalog and then go over every area thats off of 128/128. Once you get things decently close, as in, BLM within 110-144, you can lock the BLM at 128 using the min/max numbers set to 128, and tune with the INT only. Since int is immediate, you can get a good idea of exactly what the fueling needs to be.
Now, under flags, you can set or unset options. Word 5, flag 7 is Lean Cruise option. Turn this off for tuning, on when you are done. This can give you better gas milage on the highway or at constant speeds by making the AF ratio 15.4:1 (you can change this too but it can be risky).
Other items, fan turn on times, under constants > fan. Its in C, so you have to convert. I set the turn on time 10-15 degrees higher than the stat, but you can see what your car runs at while driving around, and go from there. You don't want it on all the time, or too easy to turn on. That and as the stat ages, it will not be so accurate either. 10-15 gives you room. I also turn them off 5 degrees cooler.
Turning off the EGR is under constants > egr, down the list a bit to If coolant <= this- disable egr. Set that to as high as it goes to turn the EGR off completely.
Depending on your application/mods, your starting point will vary. If you change the injectors or fuel pressure, your first goal is to go to the Tables > Fuel > BPW vs Desired EGR. This is your fuel constant. There is math involved, but I hate math:P If you turn off the EGR, this is a simple 1 setting change, at the 0 position for no EGR. Raising the number = smaller injectors. Im used to doing this with the real number, not the actual converted number GMPCM gives you. Anyway, you change this until the car is tunable basically. If you set it till your idle is decent (not dead on persay, it could be rich or lean, but as long as its in the idle range you are fine).
After the constant is set, the next goal is to tune idle. You have to watch the BLM and INT values. BLM is long term fuel, INT is short term. At idle, this is easy to watch as your INT will move first, and as it sits above or below 128, the BLM will slowly start moving in the same direction as the INT. Eventually, unless the fueling is out of bounds of the programmed range (you can set min and max values for int and blm), the INT will sit at 127-129 and the BLM will stay. If the BLM is over 128, you need to add some fuel. If its under, you cut fuel. Supposedly you can take the percentage it is off from 128, and multiply your VE section by that to get the total. To do this, you have to add up the base VE (F30 table under fuel) with the 3D VE table (F29). I don't bother with the math as ive done it long enough to get a feel for how much fuel to change in the tables. For idle though, you will want to change the F29E table, or idle VE table. Again, if its out of range (can't go under 0), you can either change the fuel constant again, or go the base VE table and raise the numbers there. It does use the 400-800 table there as well in the idle fuel calculation.
After that, its cruising fuel, which is where you need to datalog and then go over every area thats off of 128/128. Once you get things decently close, as in, BLM within 110-144, you can lock the BLM at 128 using the min/max numbers set to 128, and tune with the INT only. Since int is immediate, you can get a good idea of exactly what the fueling needs to be.
Now, under flags, you can set or unset options. Word 5, flag 7 is Lean Cruise option. Turn this off for tuning, on when you are done. This can give you better gas milage on the highway or at constant speeds by making the AF ratio 15.4:1 (you can change this too but it can be risky).
Other items, fan turn on times, under constants > fan. Its in C, so you have to convert. I set the turn on time 10-15 degrees higher than the stat, but you can see what your car runs at while driving around, and go from there. You don't want it on all the time, or too easy to turn on. That and as the stat ages, it will not be so accurate either. 10-15 gives you room. I also turn them off 5 degrees cooler.
Turning off the EGR is under constants > egr, down the list a bit to If coolant <= this- disable egr. Set that to as high as it goes to turn the EGR off completely.
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