discostu
07-20-2007, 11:29 AM
This data was gathered by 91chevZ71, through correspondence from fullsizechevy.com and thirdgen.org. This should be a sticky.
TBI Tuning Guide
PROM ID
Prom ID is useless at this point. It was used to ID a chip or calibration when datalogging. If you want to use it, do it, but NEVER forget to update it or it'll ruin that whole idea of organizing calibrations with datalogs. Oh, and it can be any value you want to make it. It doesn't affect anything important.
Fuel Tables
The main fuel tables are added together and above 3200rpm the last row (or column?) is used with the VE #2 table. If that isn't clear let me know. Just remember that the VE #2 is ALWAYS used, not just above 3200rpm.
Fuel Correction (BLM & INT)
The BLM/INT works differently on different masks. I'm not an expert on the 7747 but with the F-body 8746 the BLM/INT would be reset to 128's when in open loop. Some masks like the TPI F-body's would reset the BLM/INT when they were below 128 but keep them if above (lean). This was a safety measure. The BLM is the long term learned correction that is multiplied into the final pulse width and the INT is the short term learned correction that is added into the final pulse width. When I say multiplied and added it isn't that direct. 1 computer byte = 256 decimal or d256. Half of that is d128. The code does a divide by 128 to come up with the multiplier and addition value for the final pulse width. So if the BLM=120, the multiple=120/128=0.94. Anything multiplied by this number makes it smaller, hence lower BLM's mean your original fuel tables are too rich for closed loop!
Open Loop Idle
Open loop idle is used when your o2 sensor is a single wire NON-heated version and/or your o2 sensor is far from the original location (y-pipe), and/or you o2 sensor has been cooling off too much when at idle. It isn't uncommon for a single wire o2 sensor to cool down too much when you decelerate and then come to a stop. There isn't much air and fuel burning in the engine to keep the o2 sensor HOT, hence open loop. If it stayed in closed loop the engine would run funky IF the o2 sensor cooled down too much. I highly recommend installing a heated o2 sensor. This way you can keep closed loop idle.
Be careful with "lean idle AFR at open loop". Don't touch that OR the AFR vs. CTS and AFR vs. Vac tables. These tables all tie together in a funky way. Basically speaking, the idle AFR constant is used in place of the AFR vs. Vac table. If you look at the stock engine vacuum at idle, then look up the value in the AFR vs. Vac table they should be similar to the idle AFR constant. This constant is used to lean out the idle, which can save gas and smooth the engine out. I don't like to lean out my motor because it would then hesitate ever so slightly at throttle tip in. Just didn't feel responsive enough. So in other words, don't touch until you know what it does :)
Yes, the max AFR caps the AFR so it doesn't run too lean.
Open Loop
The engine will operate in open loop warm when you go WOT. It won't, however use the open loop AFR's but instead will use the PE AFR. Other times the engine will run in open loop mode are highway mode, decel enlean, and DFCO (decel fuel cut-off). Basically when-ever you want an AFR OTHER than stoich (14.7). Highway mode uses a leaner AFR to get a little bit more mpg. Usually the gains are so minimal that it isn't worth it on a heavy vehicle. Only good on light weight Camaro’s and Vette's with big engines. This is similar to DOD, which also doesn't work well with heavy vehicles.
Remember the open loop tables are added together! You're just looking at the one based on MAP. There is also the one based on TEMP. Look back in this e-mail about the PE AFR table and why the open loop AFR drops at the higher engine load/MAP. So sure that table has a 4 in it but the coolant temp table probably has a 9 or 10 in it which adds up to 13 or 14:1. I hope that clicks together. It's a hard concept to visualize but that is because this computer isn't exactly a speed demon so they saved memory by making the tables 2D rather than 3D. 2x2D tables added together are a fraction of the size of 1x3D table. It’s a royal PITA, but it’s effective.
AFR Enable Delays
Don't bother with the Open loop idle AFR enable blah blah blah. The delays should be left alone. Going lean too quickly can stall your engine if your tune isn't near perfect! And by perfect I mean GM dyno testing for months and then months of on-road testing so yeah, don't mess with these values.
Initial Spark Advance
Initial Spark advance is your base timing. Whatever your distributor is set at set this to the same. If you don't and let's say you have 4 degrees of base timing, well how in the world is the ECM going to know this? All of your SA values won't be TRUE engine SA (remember SA stands for spark advance). This is very important if you have too much timing in a table and the ECM limits your max SA to 42 degrees. If your initial is still at 0 then when the limiter gets hit your engine would have actually experienced 46 degrees of SA!!!
Extended Spark Slope
The rest of the constants you seem to grasp. I won’t use the extended RPM slope. Set it to zero and just use the Main SA table. You should have all of your timing in by 3600rpm anyways and the extended would just be hard to visualize."
Main Spark Bias
The main spark bias is subtracted from the total timing table. Depending on the xdf file you're using it might already be taken into consideration when you view the main spark table.
Spark Compensators
The cool compensation spark gives more timing when the engine is cold. It also removes some timing if your engine is overheating. The reason for adding SA at colder temps is 2 fold. 1st reason is to quickly heat up the engine. When running a cold engine it's usually in open loop for a WHILE. This is when you want heat FAST so by advancing the timing it burns more of the fuel in the combustion chamber and less heat goes out the exhaust. This warms up the coolant (engine) which gives you heat faster. The other reason it runs more timing is because it can! A cold/cool combustion chamber can handle more timing without detonating. This is because the combustion pressure's CAN be higher without pinging (detonation from heat). Ideal gas law says if volume stays constant, and pressure increases, so does temperature. Hence the reasons power adder vehicles can only use a very little bit of SA. It's the same reason the LS1's only run mid to low 20's on WOT SA. They are filling the combustion chambers with a LOT of volume so they don't need and can't USE the extra SA to make more power. What ever you do, don't think you need more SA to make more power. The better the engine, the less SA it needs :) . Your coolant SA table might show a dip. This is for EGR. Flatten it out. If that doesn't make sense don't worry, I'll send you a bin file later that shows the difference. By retarding the SA in the "warm" area of the table it helps EGR. I can go into more details but it is very confusing.
Power Enrichment
PE stands for Power Enrichment. The delay isn't really desired unless you tow and/or have a cat still in the exhaust stream. Even then, if you just have a cat it would probably be a good idea to remove the delay by setting it to 0.
PE mode gets evoked based on the amount of throttle position vs. engine RPM (PE evoke TPS vs. RPM?). In other words, yes, PE mode is pretty much only on at WOT or near WOT. At lower RPMs it is evoked sooner.
PE Spark
PE does only add spark, it can't remove it. I zero this table out. It's useless in most healthy engines. Just use the main SA table. WOT or PE mode usually takes place in the 90-100kpa rows (or is it columns?). Letting off the throttle brings a vacuum usually in the 20kpa area. This can help slow down a vehicle :) . Remove timing in the main SA table in the 20kpa area's and it'll engine break more. Too much retard and it'll back fire through the exhaust.
Entering PE
Yes, TPS vs. RPM for PE is just as it sounds. For better mpg, raise the lower RPM values to the 70's or even 80's. For more "fun", lower all of the values to below 50. Something in the 30's is as low as I'd go.
PE AFR
PE AFR vs. RPM is the desired (target) AFR for PE mode but it assumes that your VE tables and injectors bpw are correct. So even if you command a 12:1 that value could be way off. You can make a nice curve with this and just use the VE table's to get a good PE AFR. This table is NOT used if you haven't bee in closed loop yet. What this means is that if you start up your engine cold, and go WOT before ever getting the o2 sensor hot enough, it will be using the open loop AFR tables (combined like we talked about). That is why if you look the open loop AFR tables add up to very low values at high manifold pressure (90-100kpa). Keep this in mind so you know how to go about "fixing" an issue like a cold engine back-fire through the intake. I had this for a while until I understood how it worked. I was spending my time richening up the PE AFR table when it was my Open Loop AFR tables that were too lean! A good PE AFR for a truck would depend on the TPS for PE vs. RPM. Low TPS for PE you would want to have leaner AFR's, like 13.5:1 up until about 2600rpm where as High TPS for PE would want around 12.0:1. Generally speaking it's pretty safe to set all these values to 12.5:1 and just use the VE #2 table to get your AFR's richer or leaner. Either way works, only draw back to using the VE #2 table is that this will also effect your low MAP (manifold air pressure, like decel or cruising) VE values that are above 3200rpm :/ . Totally up to you. I can't say I like one way more than the other.
Acceleration Enrichment
You understand the Accel Enrich (AE) so I won't indulge much more. The only trick with it is to understand that the MAP is more useful for tuning back fire through the intake issues. When it back fires through the intake it is almost always because of not enough AE. You can try increasing the TPS AE but I find the MAP AE to do better with that. Too much TPS AE and it'll load up the engine (with fuel) when you're driving spirited on a cold/cool motor. Also note that the AE is based on pulse width!!! This is critical to visualizing AE. When you change your bpw your AE fuel volume with also change, even though you didn't touch those tables. Same goes for it you change the physical injector flow rates with either bigger injectors or fuel pressure changes. Increasing either and not re-adjusting the AE tables will RICHEN up your tip-in. Keep that in mind when you start tuning the AE. You'll often have to come back to this unlike the SA tables. For the most part, you can set the SA tables up to be safe and it'll run 90-95% optimal with 4-6 degrees less than its peak tolerance. Example; you won't loose much power if you program in 28 degrees of total WOT timing and just leave it there while you work on getting the AFR's correct. Then once the fuel is correct, you'll come back to the SA and creep up on it :) . That's the name of the game, back and forth, not both at the same time or you won't know which helped and which hurt! You'll waste more time if you try and save time. The bin I send you will run well and shouldn't require more tweaking so you had better take your time focusing on one issue :) . Ok, back to the tables...
Cranking AFR
Don't touch the crank AFR vs. temp. This is used independently of the open loop tables but IS used with the VE tables!!! In fact all of the open loop tables still assume the VE tables are correct. This mean the VE tables affect a LOT :) and require a good amount of initial tuning. When you learn in the VE tables based on the BLM's you'll notice that you won't hit every cell, in fact you won't even come close to some of them. In these cases it's safe to extrapolate. So assume that at lower RPM's below peak engine torque, the VE will be less, same with above peak torque. Then assume that higher MAP values will always be higher than lower MAP. A peaky pitfall VE table is bad. It should be smooth like a hill, not a rocky mountain. Also note that VE follows your torque curve. The peak torque comes very close to peak VE.
Back to cranking AFR: if you want, you can lean these tables out a little bit if you find your engine is flooding after start-up. Though if it's flooding, you might look at the VE or injector constant first because truly the stock cranking AFR table shouldn't flood an engine ;) . Increasing the values isn't abnormal after you've done a lot of VE closed loop tuning and want the engine to startup with less cranking. For now, leave it alone and hopefully you'll never need to touch it.
Idle Air Control
IAC steps vs. CTS is to increase engine rpm when it's cold. This again is 2 fold. The 1st reason is to heat up the engine; the 2nd is to prevent stalling like you said. You're right, cold engines need more air but only if you want to heat them up faster. I had my engine running so well that it's cold start-up RPM was 900rpm. I did this because I hated how my transmission felt when going from park to drive with higher RPM’s. You can lower these steps and I advise that you do right off the bat. The best TBI idle is with little to no IAC steps (higher steps = higher air flow). This is because the IAC by-passes the butterfly's and that is bad because the fuel is then sitting on the throttle blades and the engine goes a little lean/rich then lean/rich again and again while the fuel puddles and drips off the throttle blades. By lower the IAC and using more throttle you'll atomize the fuel better with all of the engine air-flow going past the throttle blades. The more air going past the throttle blades the higher the velocity which is the same reason small carbs "feel" better at idle and cruising! So at your ideal operating temp, set the IAC steps to 0 and then increase them at engine over temp (raises water pump flow rate) and increase them at lower engine temps. I would just subtract from the whole stock table what-ever it takes to get a 0 at your ideal engine temp. Then you'll probably need to take a screw-driver and re-set your min idle. Don't worry about the TPS voltage!!! That is self-correcting :) . The ECM looks at the lowest TPS voltage as zero percent so when-ever the ECM is powered on, like before engine cranking even begins, it looks at that TPS value and says THAT is "0%". Even when you crack the throttle open with your foot and crank, when-ever you lift off, it'll find that new lower value and make it the new reference point for 0%. It's still a good idea to adjust the TPS sensor to get a lower voltage like around .6 on a hot engine idle. The other way to quickly get an ideal min-idle screw setting is to set the min-idle screw while watching the IAC steps (counts, what-ever you want to call them). Opening up the throttle blades will bring down the IAC steps because it'll be trying to aim for the target idle RPM. Low IAC counts at a hot engine idle = perfect. Low would be anything below 20 or better yet, 10. Zero should be avoided so that the IAC doesn't get stuck closed which it can do if it's dirty. Don't you love how complicated this stuff gets. This is almost as complicated as the Iraq war but a little more scientific.
Idle Air Control Timer
IAC park position is meant for start-up. Don't mess with this value. You can try and lower it but it might effect your engine's starting. It doesn't affect idle speeds.
Warm closed loop delay timer is used for how long before closed loop operation after a warm engine restart. Cold same thing, just replace warm with cold is that last sentence.
Target Idle RPM
The target idle RPM is only used with closed loop. Open loop uses the IAC steps vs. CTS table.
EGR
EGR stuff = useless, so zero them out.
Base Pulse Width
BPW is relative. There are good calculations but the basic idea is larger injectors/engine size = lower number and vice versa.
BPW Constant
BPW constant vs. airflow vs. egr d/c is because the EGR causes air-flow into the combustion chamber that isn't accounted for by the MAP sensor. Without EGR, you don't need to touch this :) .
Torque Converter Clutch
TCC is really simple. Basically speaking you only want it to engage at low TPS. If you try and have it on at higher TPS and WOT you can destroy the clutch material and have it load up the trans with clutch particles. They just aren’t strong enough unless you get a multi-plate aftermarket design.
Highway Mode
Highway mode is an open loop mode that is used to lean out the engine to increase fuel economy. It does work but at the risk of burning up the piston rings and over-heating the engine oil. When you lean out an engine you then have to add more timing because lean = burn slow and when you add more timing more heat goes into the combustion chamber! Inside the combustion chamber you have the heads and the pistons. Lucky for the valves, head gaskets, and cylinders they are cooled directly by the engine coolant. The pistons on the other hand aren't so fortunate. They only get cooled by the oil! More heat in the combustion chamber = more heat going into the oil so when using highway mode it's best to have an oil temp gauge that you can monitor. Highway mode has 2 sub modes, fuel and spark. The highway fuel can be evoked without highway spark but most of the time they come together at the same time. The highway mode SA is stupid. Don't use this, just zero out that table and use the main SA table to have your "cruising" SA. A normal value is around 38-44 degrees but with vortec heads and a truck I'd go with 38-40 max in the main SA table.
TBI Tuning Guide
PROM ID
Prom ID is useless at this point. It was used to ID a chip or calibration when datalogging. If you want to use it, do it, but NEVER forget to update it or it'll ruin that whole idea of organizing calibrations with datalogs. Oh, and it can be any value you want to make it. It doesn't affect anything important.
Fuel Tables
The main fuel tables are added together and above 3200rpm the last row (or column?) is used with the VE #2 table. If that isn't clear let me know. Just remember that the VE #2 is ALWAYS used, not just above 3200rpm.
Fuel Correction (BLM & INT)
The BLM/INT works differently on different masks. I'm not an expert on the 7747 but with the F-body 8746 the BLM/INT would be reset to 128's when in open loop. Some masks like the TPI F-body's would reset the BLM/INT when they were below 128 but keep them if above (lean). This was a safety measure. The BLM is the long term learned correction that is multiplied into the final pulse width and the INT is the short term learned correction that is added into the final pulse width. When I say multiplied and added it isn't that direct. 1 computer byte = 256 decimal or d256. Half of that is d128. The code does a divide by 128 to come up with the multiplier and addition value for the final pulse width. So if the BLM=120, the multiple=120/128=0.94. Anything multiplied by this number makes it smaller, hence lower BLM's mean your original fuel tables are too rich for closed loop!
Open Loop Idle
Open loop idle is used when your o2 sensor is a single wire NON-heated version and/or your o2 sensor is far from the original location (y-pipe), and/or you o2 sensor has been cooling off too much when at idle. It isn't uncommon for a single wire o2 sensor to cool down too much when you decelerate and then come to a stop. There isn't much air and fuel burning in the engine to keep the o2 sensor HOT, hence open loop. If it stayed in closed loop the engine would run funky IF the o2 sensor cooled down too much. I highly recommend installing a heated o2 sensor. This way you can keep closed loop idle.
Be careful with "lean idle AFR at open loop". Don't touch that OR the AFR vs. CTS and AFR vs. Vac tables. These tables all tie together in a funky way. Basically speaking, the idle AFR constant is used in place of the AFR vs. Vac table. If you look at the stock engine vacuum at idle, then look up the value in the AFR vs. Vac table they should be similar to the idle AFR constant. This constant is used to lean out the idle, which can save gas and smooth the engine out. I don't like to lean out my motor because it would then hesitate ever so slightly at throttle tip in. Just didn't feel responsive enough. So in other words, don't touch until you know what it does :)
Yes, the max AFR caps the AFR so it doesn't run too lean.
Open Loop
The engine will operate in open loop warm when you go WOT. It won't, however use the open loop AFR's but instead will use the PE AFR. Other times the engine will run in open loop mode are highway mode, decel enlean, and DFCO (decel fuel cut-off). Basically when-ever you want an AFR OTHER than stoich (14.7). Highway mode uses a leaner AFR to get a little bit more mpg. Usually the gains are so minimal that it isn't worth it on a heavy vehicle. Only good on light weight Camaro’s and Vette's with big engines. This is similar to DOD, which also doesn't work well with heavy vehicles.
Remember the open loop tables are added together! You're just looking at the one based on MAP. There is also the one based on TEMP. Look back in this e-mail about the PE AFR table and why the open loop AFR drops at the higher engine load/MAP. So sure that table has a 4 in it but the coolant temp table probably has a 9 or 10 in it which adds up to 13 or 14:1. I hope that clicks together. It's a hard concept to visualize but that is because this computer isn't exactly a speed demon so they saved memory by making the tables 2D rather than 3D. 2x2D tables added together are a fraction of the size of 1x3D table. It’s a royal PITA, but it’s effective.
AFR Enable Delays
Don't bother with the Open loop idle AFR enable blah blah blah. The delays should be left alone. Going lean too quickly can stall your engine if your tune isn't near perfect! And by perfect I mean GM dyno testing for months and then months of on-road testing so yeah, don't mess with these values.
Initial Spark Advance
Initial Spark advance is your base timing. Whatever your distributor is set at set this to the same. If you don't and let's say you have 4 degrees of base timing, well how in the world is the ECM going to know this? All of your SA values won't be TRUE engine SA (remember SA stands for spark advance). This is very important if you have too much timing in a table and the ECM limits your max SA to 42 degrees. If your initial is still at 0 then when the limiter gets hit your engine would have actually experienced 46 degrees of SA!!!
Extended Spark Slope
The rest of the constants you seem to grasp. I won’t use the extended RPM slope. Set it to zero and just use the Main SA table. You should have all of your timing in by 3600rpm anyways and the extended would just be hard to visualize."
Main Spark Bias
The main spark bias is subtracted from the total timing table. Depending on the xdf file you're using it might already be taken into consideration when you view the main spark table.
Spark Compensators
The cool compensation spark gives more timing when the engine is cold. It also removes some timing if your engine is overheating. The reason for adding SA at colder temps is 2 fold. 1st reason is to quickly heat up the engine. When running a cold engine it's usually in open loop for a WHILE. This is when you want heat FAST so by advancing the timing it burns more of the fuel in the combustion chamber and less heat goes out the exhaust. This warms up the coolant (engine) which gives you heat faster. The other reason it runs more timing is because it can! A cold/cool combustion chamber can handle more timing without detonating. This is because the combustion pressure's CAN be higher without pinging (detonation from heat). Ideal gas law says if volume stays constant, and pressure increases, so does temperature. Hence the reasons power adder vehicles can only use a very little bit of SA. It's the same reason the LS1's only run mid to low 20's on WOT SA. They are filling the combustion chambers with a LOT of volume so they don't need and can't USE the extra SA to make more power. What ever you do, don't think you need more SA to make more power. The better the engine, the less SA it needs :) . Your coolant SA table might show a dip. This is for EGR. Flatten it out. If that doesn't make sense don't worry, I'll send you a bin file later that shows the difference. By retarding the SA in the "warm" area of the table it helps EGR. I can go into more details but it is very confusing.
Power Enrichment
PE stands for Power Enrichment. The delay isn't really desired unless you tow and/or have a cat still in the exhaust stream. Even then, if you just have a cat it would probably be a good idea to remove the delay by setting it to 0.
PE mode gets evoked based on the amount of throttle position vs. engine RPM (PE evoke TPS vs. RPM?). In other words, yes, PE mode is pretty much only on at WOT or near WOT. At lower RPMs it is evoked sooner.
PE Spark
PE does only add spark, it can't remove it. I zero this table out. It's useless in most healthy engines. Just use the main SA table. WOT or PE mode usually takes place in the 90-100kpa rows (or is it columns?). Letting off the throttle brings a vacuum usually in the 20kpa area. This can help slow down a vehicle :) . Remove timing in the main SA table in the 20kpa area's and it'll engine break more. Too much retard and it'll back fire through the exhaust.
Entering PE
Yes, TPS vs. RPM for PE is just as it sounds. For better mpg, raise the lower RPM values to the 70's or even 80's. For more "fun", lower all of the values to below 50. Something in the 30's is as low as I'd go.
PE AFR
PE AFR vs. RPM is the desired (target) AFR for PE mode but it assumes that your VE tables and injectors bpw are correct. So even if you command a 12:1 that value could be way off. You can make a nice curve with this and just use the VE table's to get a good PE AFR. This table is NOT used if you haven't bee in closed loop yet. What this means is that if you start up your engine cold, and go WOT before ever getting the o2 sensor hot enough, it will be using the open loop AFR tables (combined like we talked about). That is why if you look the open loop AFR tables add up to very low values at high manifold pressure (90-100kpa). Keep this in mind so you know how to go about "fixing" an issue like a cold engine back-fire through the intake. I had this for a while until I understood how it worked. I was spending my time richening up the PE AFR table when it was my Open Loop AFR tables that were too lean! A good PE AFR for a truck would depend on the TPS for PE vs. RPM. Low TPS for PE you would want to have leaner AFR's, like 13.5:1 up until about 2600rpm where as High TPS for PE would want around 12.0:1. Generally speaking it's pretty safe to set all these values to 12.5:1 and just use the VE #2 table to get your AFR's richer or leaner. Either way works, only draw back to using the VE #2 table is that this will also effect your low MAP (manifold air pressure, like decel or cruising) VE values that are above 3200rpm :/ . Totally up to you. I can't say I like one way more than the other.
Acceleration Enrichment
You understand the Accel Enrich (AE) so I won't indulge much more. The only trick with it is to understand that the MAP is more useful for tuning back fire through the intake issues. When it back fires through the intake it is almost always because of not enough AE. You can try increasing the TPS AE but I find the MAP AE to do better with that. Too much TPS AE and it'll load up the engine (with fuel) when you're driving spirited on a cold/cool motor. Also note that the AE is based on pulse width!!! This is critical to visualizing AE. When you change your bpw your AE fuel volume with also change, even though you didn't touch those tables. Same goes for it you change the physical injector flow rates with either bigger injectors or fuel pressure changes. Increasing either and not re-adjusting the AE tables will RICHEN up your tip-in. Keep that in mind when you start tuning the AE. You'll often have to come back to this unlike the SA tables. For the most part, you can set the SA tables up to be safe and it'll run 90-95% optimal with 4-6 degrees less than its peak tolerance. Example; you won't loose much power if you program in 28 degrees of total WOT timing and just leave it there while you work on getting the AFR's correct. Then once the fuel is correct, you'll come back to the SA and creep up on it :) . That's the name of the game, back and forth, not both at the same time or you won't know which helped and which hurt! You'll waste more time if you try and save time. The bin I send you will run well and shouldn't require more tweaking so you had better take your time focusing on one issue :) . Ok, back to the tables...
Cranking AFR
Don't touch the crank AFR vs. temp. This is used independently of the open loop tables but IS used with the VE tables!!! In fact all of the open loop tables still assume the VE tables are correct. This mean the VE tables affect a LOT :) and require a good amount of initial tuning. When you learn in the VE tables based on the BLM's you'll notice that you won't hit every cell, in fact you won't even come close to some of them. In these cases it's safe to extrapolate. So assume that at lower RPM's below peak engine torque, the VE will be less, same with above peak torque. Then assume that higher MAP values will always be higher than lower MAP. A peaky pitfall VE table is bad. It should be smooth like a hill, not a rocky mountain. Also note that VE follows your torque curve. The peak torque comes very close to peak VE.
Back to cranking AFR: if you want, you can lean these tables out a little bit if you find your engine is flooding after start-up. Though if it's flooding, you might look at the VE or injector constant first because truly the stock cranking AFR table shouldn't flood an engine ;) . Increasing the values isn't abnormal after you've done a lot of VE closed loop tuning and want the engine to startup with less cranking. For now, leave it alone and hopefully you'll never need to touch it.
Idle Air Control
IAC steps vs. CTS is to increase engine rpm when it's cold. This again is 2 fold. The 1st reason is to heat up the engine; the 2nd is to prevent stalling like you said. You're right, cold engines need more air but only if you want to heat them up faster. I had my engine running so well that it's cold start-up RPM was 900rpm. I did this because I hated how my transmission felt when going from park to drive with higher RPM’s. You can lower these steps and I advise that you do right off the bat. The best TBI idle is with little to no IAC steps (higher steps = higher air flow). This is because the IAC by-passes the butterfly's and that is bad because the fuel is then sitting on the throttle blades and the engine goes a little lean/rich then lean/rich again and again while the fuel puddles and drips off the throttle blades. By lower the IAC and using more throttle you'll atomize the fuel better with all of the engine air-flow going past the throttle blades. The more air going past the throttle blades the higher the velocity which is the same reason small carbs "feel" better at idle and cruising! So at your ideal operating temp, set the IAC steps to 0 and then increase them at engine over temp (raises water pump flow rate) and increase them at lower engine temps. I would just subtract from the whole stock table what-ever it takes to get a 0 at your ideal engine temp. Then you'll probably need to take a screw-driver and re-set your min idle. Don't worry about the TPS voltage!!! That is self-correcting :) . The ECM looks at the lowest TPS voltage as zero percent so when-ever the ECM is powered on, like before engine cranking even begins, it looks at that TPS value and says THAT is "0%". Even when you crack the throttle open with your foot and crank, when-ever you lift off, it'll find that new lower value and make it the new reference point for 0%. It's still a good idea to adjust the TPS sensor to get a lower voltage like around .6 on a hot engine idle. The other way to quickly get an ideal min-idle screw setting is to set the min-idle screw while watching the IAC steps (counts, what-ever you want to call them). Opening up the throttle blades will bring down the IAC steps because it'll be trying to aim for the target idle RPM. Low IAC counts at a hot engine idle = perfect. Low would be anything below 20 or better yet, 10. Zero should be avoided so that the IAC doesn't get stuck closed which it can do if it's dirty. Don't you love how complicated this stuff gets. This is almost as complicated as the Iraq war but a little more scientific.
Idle Air Control Timer
IAC park position is meant for start-up. Don't mess with this value. You can try and lower it but it might effect your engine's starting. It doesn't affect idle speeds.
Warm closed loop delay timer is used for how long before closed loop operation after a warm engine restart. Cold same thing, just replace warm with cold is that last sentence.
Target Idle RPM
The target idle RPM is only used with closed loop. Open loop uses the IAC steps vs. CTS table.
EGR
EGR stuff = useless, so zero them out.
Base Pulse Width
BPW is relative. There are good calculations but the basic idea is larger injectors/engine size = lower number and vice versa.
BPW Constant
BPW constant vs. airflow vs. egr d/c is because the EGR causes air-flow into the combustion chamber that isn't accounted for by the MAP sensor. Without EGR, you don't need to touch this :) .
Torque Converter Clutch
TCC is really simple. Basically speaking you only want it to engage at low TPS. If you try and have it on at higher TPS and WOT you can destroy the clutch material and have it load up the trans with clutch particles. They just aren’t strong enough unless you get a multi-plate aftermarket design.
Highway Mode
Highway mode is an open loop mode that is used to lean out the engine to increase fuel economy. It does work but at the risk of burning up the piston rings and over-heating the engine oil. When you lean out an engine you then have to add more timing because lean = burn slow and when you add more timing more heat goes into the combustion chamber! Inside the combustion chamber you have the heads and the pistons. Lucky for the valves, head gaskets, and cylinders they are cooled directly by the engine coolant. The pistons on the other hand aren't so fortunate. They only get cooled by the oil! More heat in the combustion chamber = more heat going into the oil so when using highway mode it's best to have an oil temp gauge that you can monitor. Highway mode has 2 sub modes, fuel and spark. The highway fuel can be evoked without highway spark but most of the time they come together at the same time. The highway mode SA is stupid. Don't use this, just zero out that table and use the main SA table to have your "cruising" SA. A normal value is around 38-44 degrees but with vortec heads and a truck I'd go with 38-40 max in the main SA table.