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Thread: Car is ignoring my torque table changes

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    Tuner in Training OverNightPartsFromJapan's Avatar
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    Car is ignoring my torque table changes

    Despite my best efforts to adjust the torque tables to accomodate error logs, the car does not respond to my torque table changes. Ive locked map point to OP for this trial, i am logging etc error vs load, and engine speed which is the same as the torque tables to show where im having torque discrepancies. When reaching loads of 70% im getting heavy throttle oscilations from what i assume are torque related disagreements. I am manually adjusting the torque table in attempt to reduce this disagreement, however no changes have any impact. Any siggestions? Ive tried torque values ranging from 0-700 with seemingly no impact to drivability.

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    Senior Tuner CCS86's Avatar
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    I think the TQ inverse table is actually more heavily used for driver demand than the TQ tables.

    No one on the forum has conveyed an understanding of how driver demand works, how to properly tune out IPC TQ errors, etc; which matches the testing results I have seen.

    I honestly think you are better off running stock GT TQ/inverse tables, with a little load rescaling at the top if you need it.

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    Quote Originally Posted by CCS86 View Post
    I think the TQ inverse table is actually more heavily used for driver demand than the TQ tables.

    No one on the forum has conveyed an understanding of how driver demand works, how to properly tune out IPC TQ errors, etc; which matches the testing results I have seen.

    I honestly think you are better off running stock GT TQ/inverse tables, with a little load rescaling at the top if you need it.
    Its been covered pretty extensivly by people here and on a few tuner schools as well. Though the schools didnt say much about it other than "you need a dyno"

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    Senior Tuner veeefour's Avatar
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    Quote Originally Posted by CCS86 View Post
    I think the TQ inverse table is actually more heavily used for driver demand than the TQ tables.

    No one on the forum has conveyed an understanding of how driver demand works, how to properly tune out IPC TQ errors, etc; which matches the testing results I have seen.
    Nope, ECU looks for torque which is calculated from load...

    Wrong, many have a good understanding on how the Fords's torque model works - including me.

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    Air, fuel, and spark gives you torque. The model is not that hard to understand.

    Air starts at the MAF, Or MAP sensors. The various models and calculations arrive at an estimated cylinder air charge.
    Fuel is modeled in the injector data. It matches that cylinder air charge in your commanded stoich ratio. It is corrected by o2 sensors closed loop and openloop corrections for changes in airflow that would happen faster than O2 sensors could predict.

    Spark is where most people get lost, or make changes that don't reflect whats happening in reality, throwing off the torque model. Air and fuel are usually well taken care of by the ECU unless you have some physical problem or made some poor calibration changes. You have MBT and borderline base tables. You have correction tables to these values. Then you have limits. You also have the entire knock strategy that happens when the engine is detonation limited. You also have a separate spark control strategy for idle and return to idle thats based around a percentage of MBT to produce a desired RPM.

    Grossly simplified to the major part of it, the torque model basically describes the torque the engine would make at the MBT spark values you have input. Minimum timing for best torque. Airflow gives you load, torque is going to be directly proportional to this as it is to manifold pressure. lambda also has an effect but to a much lesser degree as it shouldn't stray too far from lambda 1 or WOT lambda values. This model can then be manipulated to compensate for pumping loss, friction, etc. to provide an even more accurate torque value. It can be used to make sure the engine is performing as it should be, not making too little or too much power. Measured values of air, fuel, and spark can be compared to this model to estimate the torque the engine is actually making. Driver demand tables describe what a position of the pedal for a given rpm means in torque, this gives the ecu what the driver wants the engine torque to be at. The ecu tries to satisfy the driver, but if it detects some thing wrong it has the ability to override this request. The torque values are also used to control much of the automatic transmission/TCC operations.

    Paying attention to your sources will point you to what is causing your issue. When you make changes you should be looking for those changes in your logs. If you don't see any thing change, you either are not logging the correct channels, not truly flashing your changes as you need to do a write entire, or are having some other scanner issue. If you do see the changes, but are still having the issue, then what you changed probably isn't the cause. ETC error can be caused from other things beside torque, TPS voltages being out of calibration, physical problems with the gears, motor, or bearings. The TPC itself is very sensitive, more so in later models, just having an older/high mileage TB thats a little dirty and sticky can result in small error you cant get rid of with the calibration.

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    Tuner in Training OverNightPartsFromJapan's Avatar
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    Quote Originally Posted by CCS86 View Post
    I think the TQ inverse table is actually more heavily used for driver demand than the TQ tables.

    No one on the forum has conveyed an understanding of how driver demand works, how to properly tune out IPC TQ errors, etc; which matches the testing results I have seen.

    I honestly think you are better off running stock GT TQ/inverse tables, with a little load rescaling at the top if you need it.

    I actually agree with this, not to imply everyone else in here is wrong. I would say I have spent the better part of 20 hours researching torque manipulation and I find plenty of people who understand the inner workings of the torque calculations but to what degree? I am a genuine believer that if you ask how or why enough you will always find the limits of what people actually know and I find plenty of "what is happening" all over this forum but no "how to manipulate it" or "why this change impacts the tune in this way" type of information. I am sure you all do understand it, just like a metallurgist understands that he needs a welder to avoid the creation of martensite for a particular purpose on a job. The welder doesn't have a clue what martensite is but he knows how to avoid it's characteristics from experience. It takes both to create the product and I see plenty of "metallurgists" on this forum. I hope that did not come off as negative, as I did not intend for it to.

    I understand that a dyno is needed to have these values accurate, but imo, the name of accuracy went out the door when I started manipulating the maf signal to make the car run right. We are talking about a car with half its sensor values being inferred and our quick and dirty method to tune the car is to use the MAS, the most important sensor, as a global scaler. Sure it works and hell I can even manipulate numerous other settings to make my airflow model seem accurate again, but something somewhere in the tune is still going to be inaccurate. My goal is to have a car that is enjoyable to drive again, and it would seem torque manipulation is my current roadblock, not accuracies.

    If the car knows there is a torque disagreement, then I see no need to dyno to obtain the correct torque values. One, because the car isn't running well enough to capture any accurate torque reading and two, if the car is aware its wrong, it will be aware when it is right after manipulation of whatever needs to be changed. My problems stem from the fact that the car is aware of the torque errors, not the fact that they actually exist. At this point in time I'm not terribly concerned with their accuracy so much as manipulating them to reduce my throttle surge and prevent the car from going into limp mode. Once I get the car to listen to my changes I will delve further down the accuracy hole.

    Back to my specific problem, I simply do not understand how I am having torque disagreements within the ecu and changing the torque values have no impact. My original post stems from the fact that I was originally going into limp mode at 50% to 120% loads but WOT and low load driving was fine. I logged throttle error along with torque errors and notice they seemed directly related. I have a stock gt500 throttle body with its calibration data pulled directly from the repository on a stock gt500 tune so it seemed logical to attempt to change torque values. I tried changing them by 20 ft/lb increments using the inverse calculator, flashing, and recreating the same rpm/load scenario. Regardless of what the torque values were changed to the errors never lessened. I thought perhaps the deviation between the current driver demand table on the car and the torque table could be so large that I could not reach an agreement between the two which was why even at values of 100 or 700 tq I saw no reduction or increase in errors. In a fit of anger, I dropped in the gt500 driver demand table and to my surprise, the car no longer went into limp mode. The errors were slightly lessened but still could not be changed by changing values on the torque and inverse tables. Could this be from the same scenario I described earlier where the difference between the dd tables and torque tables are so great that changing the torque tables cannot compensate? Thank you all very much for your input and thank you for the detailed explanation Murfie.

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    One thing, since almost all the calculations rely on the torque model, and the torque model must know the amount of air coming in, when we scale the MAF sensor we mess up the actual airflow. Add to the fact that with a larger hole or tube to mount the sensor in, to keep sensor from maxxing out, there is no way the airflow is anywhere correctly metered into the ecu. We are working around this in the tuning, but it doesn't matter, as if it gets dialed in, it works. On mine, I have the JLT super big tube, my A/F ratio swings around some under low rpm, low loads, I'm thinking that there is air going into the motor that is not metered accurately, in other words air is going around the sensor, since the sensor is mounted in such a big hole. No way the computer can know this, but this must be done to use the meter we currently have.
    So, if the ecu doesn't accurately know the amount of air going in, it cannot know how much to open the tb to get the correct amount of air in. I think this is why we have throttle errors sometimes. Mine will have as much as 1? or so, but it seems ok like that. I know stock cars tend to run less than one, which is expected with stock size tb & MAF sensor, & cams.

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    Quote Originally Posted by MRRPMBRP View Post
    One thing, since almost all the calculations rely on the torque model, and the torque model must know the amount of air coming in, when we scale the MAF sensor we mess up the actual airflow. Add to the fact that with a larger hole or tube to mount the sensor in, to keep sensor from maxxing out, there is no way the airflow is anywhere correctly metered into the ecu. We are working around this in the tuning, but it doesn't matter, as if it gets dialed in, it works. On mine, I have the JLT super big tube, my A/F ratio swings around some under low rpm, low loads, I'm thinking that there is air going into the motor that is not metered accurately, in other words air is going around the sensor, since the sensor is mounted in such a big hole. No way the computer can know this, but this must be done to use the meter we currently have.
    So, if the ecu doesn't accurately know the amount of air going in, it cannot know how much to open the tb to get the correct amount of air in. I think this is why we have throttle errors sometimes. Mine will have as much as 1? or so, but it seems ok like that. I know stock cars tend to run less than one, which is expected with stock size tb & MAF sensor, & cams.
    Not starting an argument or anything; just curious...... but don't you think the swinging would be caused by turbulence in the tube?

    MAF sensors heat an element/diode and measure the voltage drop required to keep the element heated which is then (by ford) turned into a sampling rate that we see in the MAF transfer function.

    So, wouldn't that mean we are measuring the velocity of that airmass and not the actual quantity of molecules entering the manifold? If that is true then that would be an explanation to Fords Statistical SD system and why it is compounded with a traditional MAF sensor. SO; that would mean you could eliminate the swinging in cmd vs actual by appropriately calibrating the SD system and with a total of 26 iterations of the same process, it would be possible to scale and calibrate them so that under just about any condition you would not see the same issue arise.......... or at least in a perfect world that would be the situation.

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    Could be turbulence for sure, but the end result would or is the same, unmetered air entering the motor. At least that's my thinking anyway.

    I think the way it works is that a certain airmass will flow through a certain orifice at a certain pressure. This airmass will cool a certain wire a certain amount, at a certain velocity (speed). This info is used to calculate the airmass going into the motor.

    I think that in a large tube, one side of the air is flowing faster than the air on the metered side, so the meter has no way to know what's happening so far away. This air could be tumbling, spinning, or whatever, & the meter wouldn't know it, since it's so far away.

    The only way I would know how to fix this is to use two meters & divide up the flow somehow in the ecu. In other words, we need the tube diameter smaller to get a better sample of what's going through the tube.

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    The sensor works and is very accurate no matter the size of the pipe, if air flow is laminar you only need the one, and if its not more sensors wont help. A smaller pipe will be easier to get laminar air flow through it at lower air flow. Just don't kid yourself into thinking a 123mm or even a 149mm MAF housing is untunable or even inaccurate. The hardest part is when not much air is flowing through it, like at idle, and there are many cars out there running these housings and idling very close to lambda as they should. It starts at the MAF, but there are so many other models and correction factors both before and after it makes it into the combustion chamber. Get the curve close, keep the sensor clean, don't use bad injector data for your fuel system setup. Let the ECU work it out, you will have no trouble.
    Last edited by murfie; 11-13-2018 at 11:56 PM.

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    Quote Originally Posted by murfie View Post
    The sensor works and is very accurate no matter the size of the pipe, if air flow is laminar you only need the one, and if its not more sensors wont help. A smaller pipe will be easier to get laminar air flow through it at lower air flow. Just don't kid yourself into thinking a 123mm or even a 149mm MAF housing is untunable or even inaccurate. The hardest part is when not much air is flowing through it, like at idle, and there are many cars out there running these housings and idling very close to lambda as they should. It starts at the MAF, but there are so many other models and correction factors both before and after it makes it into the combustion chamber. Get the curve close, keep the sensor clean, don't use bad injector data for your fuel system setup. Let the ECU work it out, you will have no trouble.

    For sure up to a point, as if we were to put the sensor in an 8ft pipe, of the same length, guarantee it wouldn't meter the air correctly as it does now at idle.
    On mine, it has a super big tube, cams, and large tb, the worst combo to make idle nicely, but it does still. I did notice a difference in A/F ratio control when I installed the super big tube, compared to the smaller one it had. Not a difference of rich or lean, but of being able to keep A/F where it was commanded, low rpm, part throttle light load, where airflow is very slow through the sensor. Seems to swing around a good bit, with nothing changing, according to the sensors input to the ecu. It's not a problem at all, works good actually, motor sounds happy, but it still acts like unmetered air going in.

    As far as the OP's problem, I'd say he needs to adjust the throttle table, and torque table(s) to get his throttle ironed out. He doesn't say what car, tb, motor, combo he has, in this thread, but that's where I think he needs to go

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    Quote Originally Posted by MRRPMBRP View Post
    For sure up to a point, as if we were to put the sensor in an 8ft pipe, of the same length, guarantee it wouldn't meter the air correctly as it does now at idle.
    On mine, it has a super big tube, cams, and large tb, the worst combo to make idle nicely, but it does still. I did notice a difference in A/F ratio control when I installed the super big tube, compared to the smaller one it had. Not a difference of rich or lean, but of being able to keep A/F where it was commanded, low rpm, part throttle light load, where airflow is very slow through the sensor. Seems to swing around a good bit, with nothing changing, according to the sensors input to the ecu. It's not a problem at all, works good actually, motor sounds happy, but it still acts like unmetered air going in.

    As far as the OP's problem, I'd say he needs to adjust the throttle table, and torque table(s) to get his throttle ironed out. He doesn't say what car, tb, motor, combo he has, in this thread, but that's where I think he needs to go
    I'm sorry! posted too quickly i guess, tuning a 2013 5.0 with a stock GT500 60mm throttle body, JLT 123mm intake, MU52lb injectors, with an Eaton m122 blower. Car is honestly driving great everywhere except for this small portion of the table where it hits the load percentage and triggers disagreement. Thank you all for your input and elaborating on the matter, i greatly appreciate your time and help

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    First, I have not heard of those injectors, but make 10000% sure inj info is 10000% correct. You will have problems exactly like this, if inj info is not perfect.
    I always use ID injectors, since they have the info for their inj posted on their site. I can buy cheaper for sure, but I lose money guessing values, trying to make something work, if they are not known.

    Throttle body info should be copy & paste, but I'm sure tuning it could help drivability some.

    Make sure your dd table doesn't have some kind of big hole or bump where you're having problems too.

    Blower overdrive will change the amount of air going through the tb, and subsequently the tune, as more air goes through the tb at a given opening angle, throwing the tb model off, some. How much overdrive are you running?

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    Senior Tuner CCS86's Avatar
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    Quote Originally Posted by OverNightPartsFromJapan View Post
    I'm sorry! posted too quickly i guess, tuning a 2013 5.0 with a stock GT500 60mm throttle body, JLT 123mm intake, MU52lb injectors, with an Eaton m122 blower. Car is honestly driving great everywhere except for this small portion of the table where it hits the load percentage and triggers disagreement. Thank you all for your input and elaborating on the matter, i greatly appreciate your time and help


    Sounds like you are running a DoB kit too




    Quote Originally Posted by MRRPMBRP View Post
    First, I have not heard of those injectors, but make 10000% sure inj info is 10000% correct. You will have problems exactly like this, if inj info is not perfect.
    I always use ID injectors, since they have the info for their inj posted on their site. I can buy cheaper for sure, but I lose money guessing values, trying to make something work, if they are not known.

    Throttle body info should be copy & paste, but I'm sure tuning it could help drivability some.

    Make sure your dd table doesn't have some kind of big hole or bump where you're having problems too.

    Blower overdrive will change the amount of air going through the tb, and subsequently the tune, as more air goes through the tb at a given opening angle, throwing the tb model off, some. How much overdrive are you running?


    We are definitely not overdriving these M122s to make 10-11psi on a Coyote. I agree that a weak spot in our calibrations is the TB modeling. On an NA car, the TB make perfect sense, where a lower MAP drives more airflow (higher effective area). Throw the supercharger on and the same principle applies when the bypass is open, but as soon as it starts to close, you have increasing MAP giving you more flow (higher effective area). So, the trends revert. That said, with some tweaking of the TB model and DD table, I have it working beautifully. My absolute load trends beautifully with pedal position, which nets very predictable throttle response.

    The MU52 injectors are the stockers off the '13+ GT500 and it's another weak link in the Coyote calibration. "No one" has good data for them on a Coyote. AED refuses to tune them. Lund says they can, but in reality they can't. I'm getting pretty damn close, but the missing link right now is a functioning inferred fuel rail temp channel to log, so I can dial in the offset & slope vs rail temp tables. Anyone reading able to log that channel on a Coyote?

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    Quote Originally Posted by murfie View Post
    The sensor works and is very accurate no matter the size of the pipe, if air flow is laminar you only need the one, and if its not more sensors wont help. A smaller pipe will be easier to get laminar air flow through it at lower air flow. Just don't kid yourself into thinking a 123mm or even a 149mm MAF housing is untunable or even inaccurate. The hardest part is when not much air is flowing through it, like at idle, and there are many cars out there running these housings and idling very close to lambda as they should. It starts at the MAF, but there are so many other models and correction factors both before and after it makes it into the combustion chamber. Get the curve close, keep the sensor clean, don't use bad injector data for your fuel system setup. Let the ECU work it out, you will have no trouble.
    So when you get osciallations like MRRPMBRP is getting, you would say that is a tune issue? I am not sure I follow what you are saying about letting the ECU do the legwork. As we know, these ECU's require full characterization that is 100% accurate other wise you will end up with issues. So what defines good data from bad data? You mentioned it starts with the maf and is then 'filtered' so to speak through various other models. So where does injector data come into play in that cycle?

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    Air fuel ratios oscillate by the nature of the PID feed back control, So its not necessarily a tune issue. The cars have widebands yes, but there is still switching like a narrow band that happens to target an AFR. You can have 25% error or .5% error the ECU is always going to be working to improve AFR control. Where you call it good and bad is up to your preference and ability. The less error you get, the better the rest of the calibration can be, the more power you can make.

    Injector data is used to determine the PW that will match the in cylinder airmass from the cylinder filling air model with a fuel mass to give the desired lambda.
    Pressure differential across the injector determines its flow rate. you need to know the MAP and rail pressure accurately to get this flow rate. You also need to know the flow rate of the injector at different pressures. MAP comes from SD and manifold filling rate. Rail pressure comes from a fuel flow rate. Hopefully your injector data comes from a good flow bench. This can be very accurate in a returnless style fuel system. Once you install a return style, pressure is controlled by the regulator, the pump could flow 8lb/s or 16lb/s, as long as the engine wasn't consuming more the rail pressure would be what ever the regulator lets it be. Many people, as its a common misunderstanding, will use return style data and either have the regulator baro referenced or boost reference, leading to lots of MAF error to get lambda correct. The only accurate way to use return style data is a MAP referenced regulator. Then setting your base pressure and using the correct data for that base pressure. You can use the other methods and measure MAP and rail pressure to get the pressure differential right, you would still need to use the stock style data to have the correct flow rates for the varying pressure.

    Air load is a very good indicator of if you're close or not. 15PSI MAP(baro) should give you .9-1.05 load, 30PSI(15psi boost) map should give you 1.8-2, Etc. If you are at 10psi boost ~25 psi MAP and see 2.0 load or higher, you know the engine is not being that efficient no matter how well it is flowing air. If anything as you go higher in boost you should assume less cylinder filling efficiency. Running 2.0 load when you are really at 1.6 load puts you at different points in many tables giving you less than optimal engine performance and transmission performance.

    OP referred to 70% load being the point he experiences the problem, this is only accurate if air model and fuel model are accurate. If its more like 1.0 load where he is transition into boost and ETC vacuum should be very close to 0 and the ECU is saying .7 load where manifold should still be still under vacuum, throttle control is going to be horrible as the model is going to give an inaccurate ETC vacuum. The ECU will close the throttle to correct this, then open it back up when it determine it needs less as this will effect load when it does this.

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    Quote Originally Posted by murfie View Post
    Air fuel ratios oscillate by the nature of the PID feed back control, So its not necessarily a tune issue. The cars have widebands yes, but there is still switching like a narrow band that happens to target an AFR. You can have 25% error or .5% error the ECU is always going to be working to improve AFR control. Where you call it good and bad is up to your preference and ability. The less error you get, the better the rest of the calibration can be, the more power you can make.

    Injector data is used to determine the PW that will match the in cylinder airmass from the cylinder filling air model with a fuel mass to give the desired lambda.
    Pressure differential across the injector determines its flow rate. you need to know the MAP and rail pressure accurately to get this flow rate. You also need to know the flow rate of the injector at different pressures. MAP comes from SD and manifold filling rate. Rail pressure comes from a fuel flow rate. Hopefully your injector data comes from a good flow bench. This can be very accurate in a returnless style fuel system. Once you install a return style, pressure is controlled by the regulator, the pump could flow 8lb/s or 16lb/s, as long as the engine wasn't consuming more the rail pressure would be what ever the regulator lets it be. Many people, as its a common misunderstanding, will use return style data and either have the regulator baro referenced or boost reference, leading to lots of MAF error to get lambda correct. The only accurate way to use return style data is a MAP referenced regulator. Then setting your base pressure and using the correct data for that base pressure. You can use the other methods and measure MAP and rail pressure to get the pressure differential right, you would still need to use the stock style data to have the correct flow rates for the varying pressure.

    Air load is a very good indicator of if you're close or not. 15PSI MAP(baro) should give you .9-1.05 load, 30PSI(15psi boost) map should give you 1.8-2, Etc. If you are at 10psi boost ~25 psi MAP and see 2.0 load or higher, you know the engine is not being that efficient no matter how well it is flowing air. If anything as you go higher in boost you should assume less cylinder filling efficiency. Running 2.0 load when you are really at 1.6 load puts you at different points in many tables giving you less than optimal engine performance and transmission performance.

    OP referred to 70% load being the point he experiences the problem, this is only accurate if air model and fuel model are accurate. If its more like 1.0 load where he is transition into boost and ETC vacuum should be very close to 0 and the ECU is saying .7 load where manifold should still be still under vacuum, throttle control is going to be horrible as the model is going to give an inaccurate ETC vacuum. The ECU will close the throttle to correct this, then open it back up when it determine it needs less as this will effect load when it does this.
    Great info!

    Referencing Air Load; air load is filtered via the SD system correct? If so, since the SD system is statistical and relies on what we tell it; wouldn't that mean in higher whp vehicles that have had decent ammounts of mods and could possibly be achiving over 100% VE (which would be considered boost) would mean that you would need to rescale and recalibrate the SD system? That would need to be done with an actual MAP sensor that way an error could be calculated between what the ECU thinks MAP is and what MAP actually is via the sensor.

    ~~ OP being 70%+~~~ So if what I just said is correct, does that mean finer throttle control could be achieved via the SD system being properly calibrated and therefor telling the car that infact it is actaully is at 1.0 instead of .7?

    As well, where do Cyl WOT multiplier and MAX multiplier come into play with this? It shows the definition to be that it actually multiplies the current airmass value (which is derived from the MAF), on stock vehicles this is set to 1.10; so that means whatever the current airmass is, 10% of the total is being added on top. SO; if we set both to 1.0 (meaning no correction is being applied) that would make the whole system more accurate correct?

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    Quote Originally Posted by murfie View Post
    Air load is a very good indicator of if you're close or not. 15PSI MAP(baro) should give you .9-1.05 load, 30PSI(15psi boost) map should give you 1.8-2, Etc. If you are at 10psi boost ~25 psi MAP and see 2.0 load or higher, you know the engine is not being that efficient no matter how well it is flowing air. If anything as you go higher in boost you should assume less cylinder filling efficiency. Running 2.0 load when you are really at 1.6 load puts you at different points in many tables giving you less than optimal engine performance and transmission performance.

    OP referred to 70% load being the point he experiences the problem, this is only accurate if air model and fuel model are accurate. If its more like 1.0 load where he is transition into boost and ETC vacuum should be very close to 0 and the ECU is saying .7 load where manifold should still be still under vacuum, throttle control is going to be horrible as the model is going to give an inaccurate ETC vacuum. The ECU will close the throttle to correct this, then open it back up when it determine it needs less as this will effect load when it does this.
    Good posting.

    This is problematic in N/A engines as well especially when you go with aftermarket cams. Most would think that LOAD indicator is not important but in reality LAOD is everything in those engines.

    You can see 30' of spark and no knock activity, you can have a very good WOT lambda and good VCT angles but your car would not perform as it should because your LOAD is not correct.
    Some would just try to increase the max LOAD with multipliers but that will not solve anything. Not enough LOAD is safe in any condition because you car would just not perform as it should.
    Too much LOAD and you can grenade your engine and transmission especially boosted.
    Last edited by veeefour; 11-18-2018 at 05:01 AM.

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    Quote Originally Posted by veeefour View Post
    Good posting.

    This is problematic in N/A engines as well especially when you go with aftermarket cams. Most would think that LOAD indicator is not important but in reality LAOD is everything in those engines.

    You can see 30' of spark and no knock activity, you can have a very good WOT lambda and good VCT angles but your car would not perform as it should because your LOAD is not correct.
    Some would just try to increase the max LOAD with multipliers but that will not solve anything. Not enough LOAD is safe in any condition because your car would just not perform as it should.
    Too much LOAD and you can grenade your engine and transmission especially boosted.
    I am curious what you mean by 'too much load'?

    As far as I understand, load is absolute (depending on what PID you are looking at) which is the ratio of the ammount of air currently in the cylinder vs the theoretical max ammount the cylinder can hold a STP. So can you explain what you mean by 'too much load' in an N/A car? I get the boosted version but I'm not following wha you are saying about N/A.

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    Quote Originally Posted by txtailtorcher View Post
    I am curious what you mean by 'too much load'?

    As far as I understand, load is absolute (depending on what PID you are looking at) which is the ratio of the ammount of air currently in the cylinder vs the theoretical max ammount the cylinder can hold a STP. So can you explain what you mean by 'too much load' in an N/A car? I get the boosted version but I'm not following wha you are saying about N/A.
    Load is inferred, based on your SD model. As mentioned indicated load is far from being real - it's just what Ford believed was right. The same goes with indicated torque.

    MAF sensor is not able to tell that you filled your cylinders completely(100%) or not - this is your job, the tuner's job. This is why some tuners have good results with N/A tuning and some do not. From what I see SD model and Torque model gets overlooked most of the time, tuners thinking that timing itself will make power the old fashion way but it's not the case with Ford's ECU's.

    Most of the time you do N/A tune by raising the spark and correcting the fuel trims and you end up with 0.7 load at WOT. You can correct this with just one multiplier and bring the load to 1.1 or more. This is what most do but that is not correct especially with aftermarket cams - you are commanding more load but your SD/Torqe models are waiting for stock values. This is what I had in mind.

    Your SD model can tolerate a lot in N/A form besides your load being around 30% off. You will get moderate results but not the results you expected to have. This is why most think aftermarket cams are not worth the effort in those engines and only a few people can actually tune it correctly. This only gets worse with boost but the rules are the same. Most would like to start with boost but in reality they should tune few intakes first and learn few things before even touching a boosted car. By few intakes I mean few with good results - not just "OK it drives" like I see most of the time.
    Last edited by veeefour; 11-18-2018 at 02:28 PM.