How To Calibrate A MAF For # Injector?
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Old September 7th, 2006, 12:30 PM   #1
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How To Calibrate A MAF For # Injector?


I received a start-up program from Rick Anderson to use on Anderson Ford Motorsports PMS-III and he mentioned this note:

"MAF to be calibrated for 42 lbs injectors"

'didnt have the chance to call him & ask him about it, cuz I already filled up the set-up form mentioning that I am using an SCT Big Air 2400 90mm MAF which I thought was made for the 42# injectors, just like the 2003 Cobra. How else can I calibrate my MAF? I'd appreciate it if anybody could tell me whether I need to calibrate that, and how please.

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Old September 9th, 2006, 09:25 AM   #2
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Mass air meters are calibrated from the manufacturer to certain injector flow. If it was advertised as calibrated for 42# injectors and you've got 42's, then you're fine. You cannot calibrate the MAF yourself... but you can tune the discrepency out though it's best to make sure it was calibrated to what you want when you bought it.
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Old September 9th, 2006, 10:26 AM   #3
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Prob more than you need to know but a good read.


Mass Air Flow Sensor Facts and Findings


Introduction: The following is a compilation of information about MAF sensors and their function from mostly WWW and mail list information. It is biased towards the Ford style two wire MAF used on mostly any Ford since the early 1990s gasoline engines.

The MAF sensors used on many of today's cars primarily use the two-wire, hot/cold wire, setup to detect the mass of the air passing through it. These wires are designed to give a feedback voltage to the engine control system (EEC, PCM, ECM, whatever) using an electronic function wired into the sensor. Many misconceptions have arisen in the realm of modifying the MAF to gain power on the vehicle. Here are some facts and information to help you better understand the use and function of the system.

The MAF is a sensor. It cannot take an active role in the operation of your vehicle, which is what the PCM does. The PCM uses all of the various inputs and runs the engine according to its program. The MAF transfer function not only tells the computer how much air is coming into the motor, but the function is used to calculate load using other inputs which profiles spark and fuel. As far as sensors go, it is a somewhat complex unit. It basically uses two wires within its body to create a current draw and output based on the different characteristics of the wires. But the way these wires act in the sensor body itself can be somewhat problematic. First, there is the flow of air entering the sensor. The air stream can have many influencing characteristics that can affect the sensor's ability to give accurate output. Turbulence and velocity variations can give false output based on the original flow profile of the sensor. So let's talk about the design for a second. When the engineers at the factory incorporate the sensor into an intake system, they must not assume it to be a perfect flow of air. The air filter, air box, sensor placement and many other factors affect the true sensing capability of the sensor. This is why when a MAF transfer function, the data stored in the computer about the sensor, is derived for one vehicle it may not be identical to the transfer function for a similar vehicle with the same exact sensor. The load calculations will also vary. Likewise, the downstream inputs that can affect the sensor vary from one design to another.

A running engine creates impulses that flow upstream, intake growl noise, that are waves of air that are now impinging on the sensor from behind. In an effort to eliminate the effect of various intake feedbacks the designers use a backflow-preventor in the form of a bar across the MAF sensor cavity using a backing plate to deflect these impulses away from the sensor elements. When the engineers develop the transfer function for a system they measure the flow of the sensor in a real-life situation. Designers actually use a laser Doppler system to precisely measure the flow characteristics. Designing a single basic design that can be used across many applications is the goal so costs can be minimized. Suffice it to say that a MAF from identical cars will not be identical. The variations in the electronics that drive the sensor have some influence on the way the car runs. As a model year progresses other variables, like part lot numbers and such can cause one car to run much better than the next. If all of the variation of the sensors and devices like injectors are taken into account, you could have a marginal car to begin with. This is why some people see great gains with slight mods and others see nothing or it gets worse.

Modifying the MAF has risks as well as potential benefits. Changing the flow characteristics can cause great problems. First, let's look at the post removal issue. Removing the post does increase the flow capacity of the meter, but now has the potential for noise from the intake causing other problems. This is more important at idle and low throttle settings.
Why? The MAF transfer function is not linear. The function is flatter at low flows and increases at an increasing rate as flow increases. If there is airflow noise at the flatter portion of the curve, the noise voltage is a much greater percentage of the total voltage being sent to the computer and the computer may balk. Thus you end up with rough or poor idle. At high flows the noise can be greater but the curve is exponential and the noise is less influential. Also, the velocity of the air in the sensor with no post has dropped at the same load. This affects the load calculation that causes the injector pulses to be off the intended design. They may be better they may be worse. Cars with closed loop operation capabilities can detect the lean or rich condition caused by the change and make adjustments on the fly. Car may start rough but smooth out as you drive. As you drive in the Wide open throttle condition, open loop, the car is now only relying on the data stored in the computer and modifications, which are not "good" or beneficial, will now affect the performance of the motor. The one perceived increase in performance has to do with the fact that the original programming of the PCM is on the rich side, extra fuel for reduced wear and tear on the motor. This modification effectively leans out the mixture and provides more efficient combustion. Over the long run though, the PCM will use it's adaptive capabilities to make the mixture correct as read by the Oxygen sensors. But having changed the flow characteristics of the sensor, the flow across the elements is also changed, possible reduced. Thus the voltage would be lower and the effective flow would cause even leaner conditions. Also, load calculations will probably be off their original curve and injector pulses may be affected. One trick to provide for the change in flow of the no-post MAF is to make a proportional change in the sample tube that contains the sensor wires. Assuming you get the hole size just right, the transfer function of the MAF is still not likely to match that of the original function map in the computer. The curve could be steeper sooner or flatter later or shifted completely.

At a given MAF voltage the air coming into the meter is known through the transfer function table. Knowing that most people drive around in closed loop situations these variations are quenched by other inputs. Just unplug the MAF all together and you will see that it will run however poorly, but it is not dead. The problem with the sample tube issue is that the overall flow characteristics of the MAF are just different than before. If you were to compare the two curves against each other, they will be very close. And it seems for the most part that the increased airflow, especially at WOT, is of greater benefit than the slight miscalibration of the sensor. What has to take place is the voltage should still represent a given flow, the modification just shifts the curve to provide flows at lower throttle levels. Again this can affect load.

Other modifications can affect even a stock sensor. The airbox, inlet tube and intake tube to the throttle body will cause the system as a whole to be slightly different. Let's not get too freaked out though. Again, the benefits of these mods are often marginally good. One key thing to remember is that the closer the MAF is to the throttle body the higher the effect the intake feedback has on the meter's accuracy. The fewer restrictions you have between these parts also can cause problems, usually rough idle and poor performance at low throttle positions. Ideally get the MAF farther away from the throttle body. For the greatest benefit from any modification to the MAF, its flow characteristics must be input into the transfer function table in the PCM. Recalibrating the MAF for larger injectors works somewhat but load calculations will be wrong. Most MAFs are limited by their size as to how much they can flow, but even then you can peg the electronics.
Adding a supercharger can cause the meter to not function to its full potential if flows above the transfer function table range occur. The sample tube size can be adjusted to give a broader range than the .5v to 5.0v the current Ford sensors have. Below are two side by side lists of MAF transfer function for two different setups on the 1994 Mustang GT. The first number in the parenthesis is the voltage and the second is the airflow in KG/hr. Notice that there is a maximum flow of 932 kg/hr on the first and 882 kg/hr on the second. Model year changes or different options in the system caused the difference. Also, the curve for the first one is very similar to the second all the way up to 4.0v and then the first one climbs rapidly.

So even though these are the same model and year, just a MAF swap will cause a discrepancy in the way WOT is computed. This swap is a full swap. The sensor bodies have been very standardized. Swapping just the bodies wouldn't make as much a difference as swapping the electronics. Put the first one in the second car and at the high end the car will get a voltage that represents a flowrate less than the actual flow which is higher, it will run leaner and possibly cause detonation. Now these are just examples and to specifically say what will really happen depends on the other variables. Dirty sensor elements gives less voltage at same flow.
Dirty injectors may cause a lean condition as well as fuel pressure and volume.



U4P0 J4J1
# Mass Air Transfer Function
( 15.9998, 932.145 ) ( 15.9998, 882.085 )
( 5, 932.145 ) ( 5, 882.085 )
( 4.75, 808.577 ) ( 4.6001, 717.327 )
( 4.5, 697.683 ) ( 4.19995, 568.729 )
( 4.25, 598.512 ) ( 3.80005, 443.577 )
( 4, 510.114 ) ( 3.5, 362.466 )
( 3.80005, 446.745 ) ( 3.30005, 313.989 )
( 3.6001, 389.397 ) ( 3.1001, 270.265 )
( 3.3999, 337.118 ) ( 2.8999, 230.66 )
( 3.19995, 290.86 ) ( 2.69995, 195.491 )
( 3, 249.037 ) ( 2.5, 163.173 )
( 2.80005, 211.65 ) ( 2.3999, 148.281 )
( 2.6001, 178.381 ) ( 2.30005, 134.974 )
( 2.3999, 149.232 ) ( 2.19995, 122.301 )
( 2.19995, 123.568 ) ( 2.1001, 110.894 )
( 2.1001, 112.162 ) ( 2, 100.122 )
( 2, 101.389 ) ( 1.8999, 89.9828 )
( 1.8999, 91.2501 ) ( 1.80005, 80.7944 )
( 1.80005, 82.0617 ) ( 1.69995, 72.2397 )
( 1.6001, 65.2692 ) ( 1.6001, 64.3187 )
( 1.5, 57.9818 ) ( 1.5, 57.0313 )
( 1.30005, 44.9914 ) ( 1.3999, 50.3777 )
( 1.19995, 39.2882 ) ( 1.30005, 44.3577 )
( 1, 29.4662 ) ( 1.19995, 38.9714 )
( 0.75, 19.961 ) ( 1, 29.1493 )
( 0.600098, 15.2084 ) ( 0.899902, 25.0304 )
( 0.399902, 10.4557 ) ( 0.800049, 21.2283 )
( 0, 8.87154 ) ( 0.600098, 14.5747 )
( 0.5, 11.7231 )
( 0, 11.7231 )

To modify the MAF sensor is in all practicality a bad move without telling the computer that the flow has increased via the transfer function table. Also, modified intakes will not be as effective as presumed unless the flow changes are calculated also. The best way to increase the flow to the motor and let it know is to get the system tested or get a system that has been flow profiled and includes the ability to program the PCM. You can't just "recalibrate" the MAF. Load will be incorrect. This can effect the durability of the motor especially when WOT driving is done.

These are issues that you must take into account when debating a change to the system. There are some slight risks involved and you'll have to decide.

I hope this information proves useful. Any discrepancies are my own and you can e-mail me about it. These are only the facts presented as I see them with the information I have gathered. Richard MacCutcheon
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Old September 9th, 2006, 03:03 PM   #4
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Thanks guys!!
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Old September 10th, 2006, 09:36 PM   #5
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PMS Tuning


I have a PMS for my car to but my mass is caled for my 42's. There is a way to set up the PMS for a mass that does not match the injectors. Remember it will never be as accurate as a meter caled for the right size injectors. most companies for a nominal fee will recal the meter to match. A good website if you dont already know of it for the PMS is www.stangtuning.com scroll down to the PMS section and there is tons if info. Check it out!!!
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Old September 12th, 2006, 12:43 AM   #6
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i thougt you just changed the calibation tube inside your MAF tube ? pull the sensor off and a little tube is there. you get a diffent one made for diffent size injectors, then you done i have done this a few times
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Old September 12th, 2006, 04:05 AM   #7
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that is only correct when you are using a C&L MAF meter housing with replaceable calibration tubes.. I'm using SCT Big Air 90mm MAF I bought from V8Power.com
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Old September 18th, 2006, 10:44 AM   #8
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Zak, you need to get the transfer function input in the maf transfer function table. If the PMS does not have a provision for this, I seriously suggest not tuning with it. If you cannot properly write a matched transfer function for your maf, you will be wasting your time. The SCT and OEM mafs are not calibrated for any specific injectors, and that also, is written in the control code. The Pro-M's and the C&L's do change the meter, and it causes major problems in the control program, mainly in the form of gross load calculation "errors". I got a 2valve motor in a month ago with forced induction and a C&L "calibrated" for 42# injectors, and had to write a program for it that literally used half the load that it should have been. In laymen's terms, this car had very little variable in the fueling and timing control, and ran very lean and very advanced ignition timing, just to start with the list of problems. This car had been to several tuners, and it was obvious they could not figure this out, and is why it came to me. Needless to say, the program I wrote for it looked pretty wacky by the time I was done.

If you have the provision you should for the maf transfer function, feel free to give me an email, and I can send you the correct function table. info@swtuning.com

Now, keep in mind that I still spend a bit of time fine tuning the maf transfer function after the base numbers are in there, so DO NOT expect to just paste it in there, and not have to fine tune it. It will need to be done.

BOTTOM LINE:

You need to properly write a transfer function for the meter, in the control system.

You need to correctly input the injector constants for the injectors you are using.

You need to correctly set up the load scaling for the load your car is seeing. If you have a different size motor than stock, your load scaling will also be affected, and should be either changed, and/or taken into consideration.

Hope this helps clear things up.

jim
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Old September 21st, 2006, 04:16 PM   #9
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Thank you Jim and all of you fellows

I checked PMS, but I don't think there's anything referred to MAF transfer function in the control system.. by looking at the attached scanned data sheet from AFM, you can find that out.. it is basically Fuel & Timing adjustment at Low, Medium & High Loads at Idle, Part Throttle & WOT

you have to excuse my ignorance.. I am next to null when it comes to electronics.. I'm also registered in Stangtuning.com since January but I'm trying to figure the thing with SCT MAF's.. I sent them an email and got no replies.

I'll be in touch with you.. thanks again.
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Old September 22nd, 2006, 09:48 AM   #10
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I have a question though.... what mods do you have on your motor that you are running such a big MAF? If your running that on a basically stock motor your not getting anyting out of it. Even a modded motor doesnt need anything close to that.
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Old September 22nd, 2006, 11:09 AM   #11
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Good question..

I'm running a Kenne Bell Blowzilla supercharger 8 lbs on a forged 333 cid roller block of 9:1 CR, ported GT40 intake, AFR 185 with nitrous/blower exhaust ports, Steeda #19 cam (480"/.480" lift & 220/226 duration @ .050" with 115 LSA - I know it's a bit small), C&L 76mm true flow pipe, BBK 75 TB, 42# injectors, Accufab boost sensitive FPR, 255 LPH, all MSD, 1-5/8" shorties with 2.5" collector, H-pipe, Borla catback, Tremec TKO-600 with SPEC 3, aluminum driveshaft, 3.73 rear end, 18" wheels to come, and other accessories like Flowkooler pump, Griffin radiator, 180 thermostat.. all I can remember.
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Old September 24th, 2006, 10:14 AM   #12
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Regarding SCT's BA-2400 MAF meter, I got this reply from a gentlement in LaSota Racing (a highly recommended tuner by Kenne Bell tech support themselves):

"The BA 2400 will work with 42# injectors and those are the smallest
injectors you want to use with it. The MAF does NOT need any calibration for any injectors, but will need a retune for your car."

Just for the info..
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Old September 25th, 2006, 03:11 PM   #13
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Twinturbo Jim, you're the man! I got this response from SCT:

The big air meters are not calibrated meters. You will need to adjust your
transfer function to work in your car with your injectors with the meter
installed.

SCT Tech Support
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Old September 25th, 2006, 08:52 PM   #14
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Looks like there is no maf transfer function with point by point tuning that you need, with the PMS. I could be wrong, but I'd get with Anderson about it. If you can load the whole curve, let me know if you need the numbers. If not, it needs to be tuned (to do it properly) with a chip and tune. The "chip" is a module that houses several devices plus the memory itself, and works much like operating the car off of a D drive, instead of the C drive. The processor is instructed to get all of it's instructions from the off board module, and runs as an oem program.

FWIW, you can run any fuel injector you want to with any cobra lightning, or SCT meter. Injector size is calibrated in the software (firmware).

You are correct with your setup to be using a BA2400or BA2800 meter with what you have. It still needs tuned properly, but you are on the right track with what you have. it will end up running the 42's between 40-56 PSI when it's all said and done. At 54psi, the Ford 42's will be 50's, and sometimes they need that extra fuel. At the higher pressure, though, keep in mind that the pump may loose volume capability. As pressure increases, voume decreases. There are high pressure walbro pumps for this, and one is rated for 90psi, and the other for something like 120psi. Either will work fine. Big fuel rails and #8 fuel lines underhood will also ensure even cylinder to cylinder fuel distribution. The stock rails are not bad, but you've got a car there, and this would be best, if you have not upgraded already.

jim
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Old September 25th, 2006, 10:46 PM   #15
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Originally Posted by IcantDo55
Prob more than you need to know but a good read.


Mass Air Flow Sensor Facts and Findings


Introduction: The following is a compilation of information about MAF sensors and their function from mostly WWW and mail list information. It is biased towards the Ford style two wire MAF used on mostly any Ford since the early 1990s gasoline engines.

The MAF sensors used on many of today's cars primarily use the two-wire, hot/cold wire, setup to detect the mass of the air passing through it. These wires are designed to give a feedback voltage to the engine control system (EEC, PCM, ECM, whatever) using an electronic function wired into the sensor. Many misconceptions have arisen in the realm of modifying the MAF to gain power on the vehicle. Here are some facts and information to help you better understand the use and function of the system.

The MAF is a sensor. It cannot take an active role in the operation of your vehicle, which is what the PCM does. The PCM uses all of the various inputs and runs the engine according to its program. The MAF transfer function not only tells the computer how much air is coming into the motor, but the function is used to calculate load using other inputs which profiles spark and fuel. As far as sensors go, it is a somewhat complex unit. It basically uses two wires within its body to create a current draw and output based on the different characteristics of the wires. But the way these wires act in the sensor body itself can be somewhat problematic. First, there is the flow of air entering the sensor. The air stream can have many influencing characteristics that can affect the sensor's ability to give accurate output. Turbulence and velocity variations can give false output based on the original flow profile of the sensor. So let's talk about the design for a second. When the engineers at the factory incorporate the sensor into an intake system, they must not assume it to be a perfect flow of air. The air filter, air box, sensor placement and many other factors affect the true sensing capability of the sensor. This is why when a MAF transfer function, the data stored in the computer about the sensor, is derived for one vehicle it may not be identical to the transfer function for a similar vehicle with the same exact sensor. The load calculations will also vary. Likewise, the downstream inputs that can affect the sensor vary from one design to another.

A running engine creates impulses that flow upstream, intake growl noise, that are waves of air that are now impinging on the sensor from behind. In an effort to eliminate the effect of various intake feedbacks the designers use a backflow-preventor in the form of a bar across the MAF sensor cavity using a backing plate to deflect these impulses away from the sensor elements. When the engineers develop the transfer function for a system they measure the flow of the sensor in a real-life situation. Designers actually use a laser Doppler system to precisely measure the flow characteristics. Designing a single basic design that can be used across many applications is the goal so costs can be minimized. Suffice it to say that a MAF from identical cars will not be identical. The variations in the electronics that drive the sensor have some influence on the way the car runs. As a model year progresses other variables, like part lot numbers and such can cause one car to run much better than the next. If all of the variation of the sensors and devices like injectors are taken into account, you could have a marginal car to begin with. This is why some people see great gains with slight mods and others see nothing or it gets worse.

Modifying the MAF has risks as well as potential benefits. Changing the flow characteristics can cause great problems. First, let's look at the post removal issue. Removing the post does increase the flow capacity of the meter, but now has the potential for noise from the intake causing other problems. This is more important at idle and low throttle settings.
Why? The MAF transfer function is not linear. The function is flatter at low flows and increases at an increasing rate as flow increases. If there is airflow noise at the flatter portion of the curve, the noise voltage is a much greater percentage of the total voltage being sent to the computer and the computer may balk. Thus you end up with rough or poor idle. At high flows the noise can be greater but the curve is exponential and the noise is less influential. Also, the velocity of the air in the sensor with no post has dropped at the same load. This affects the load calculation that causes the injector pulses to be off the intended design. They may be better they may be worse. Cars with closed loop operation capabilities can detect the lean or rich condition caused by the change and make adjustments on the fly. Car may start rough but smooth out as you drive. As you drive in the Wide open throttle condition, open loop, the car is now only relying on the data stored in the computer and modifications, which are not "good" or beneficial, will now affect the performance of the motor. The one perceived increase in performance has to do with the fact that the original programming of the PCM is on the rich side, extra fuel for reduced wear and tear on the motor. This modification effectively leans out the mixture and provides more efficient combustion. Over the long run though, the PCM will use it's adaptive capabilities to make the mixture correct as read by the Oxygen sensors. But having changed the flow characteristics of the sensor, the flow across the elements is also changed, possible reduced. Thus the voltage would be lower and the effective flow would cause even leaner conditions. Also, load calculations will probably be off their original curve and injector pulses may be affected. One trick to provide for the change in flow of the no-post MAF is to make a proportional change in the sample tube that contains the sensor wires. Assuming you get the hole size just right, the transfer function of the MAF is still not likely to match that of the original function map in the computer. The curve could be steeper sooner or flatter later or shifted completely.

At a given MAF voltage the air coming into the meter is known through the transfer function table. Knowing that most people drive around in closed loop situations these variations are quenched by other inputs. Just unplug the MAF all together and you will see that it will run however poorly, but it is not dead. The problem with the sample tube issue is that the overall flow characteristics of the MAF are just different than before. If you were to compare the two curves against each other, they will be very close. And it seems for the most part that the increased airflow, especially at WOT, is of greater benefit than the slight miscalibration of the sensor. What has to take place is the voltage should still represent a given flow, the modification just shifts the curve to provide flows at lower throttle levels. Again this can affect load.

Other modifications can affect even a stock sensor. The airbox, inlet tube and intake tube to the throttle body will cause the system as a whole to be slightly different. Let's not get too freaked out though. Again, the benefits of these mods are often marginally good. One key thing to remember is that the closer the MAF is to the throttle body the higher the effect the intake feedback has on the meter's accuracy. The fewer restrictions you have between these parts also can cause problems, usually rough idle and poor performance at low throttle positions. Ideally get the MAF farther away from the throttle body. For the greatest benefit from any modification to the MAF, its flow characteristics must be input into the transfer function table in the PCM. Recalibrating the MAF for larger injectors works somewhat but load calculations will be wrong. Most MAFs are limited by their size as to how much they can flow, but even then you can peg the electronics.
Adding a supercharger can cause the meter to not function to its full potential if flows above the transfer function table range occur. The sample tube size can be adjusted to give a broader range than the .5v to 5.0v the current Ford sensors have. Below are two side by side lists of MAF transfer function for two different setups on the 1994 Mustang GT. The first number in the parenthesis is the voltage and the second is the airflow in KG/hr. Notice that there is a maximum flow of 932 kg/hr on the first and 882 kg/hr on the second. Model year changes or different options in the system caused the difference. Also, the curve for the first one is very similar to the second all the way up to 4.0v and then the first one climbs rapidly.

So even though these are the same model and year, just a MAF swap will cause a discrepancy in the way WOT is computed. This swap is a full swap. The sensor bodies have been very standardized. Swapping just the bodies wouldn't make as much a difference as swapping the electronics. Put the first one in the second car and at the high end the car will get a voltage that represents a flowrate less than the actual flow which is higher, it will run leaner and possibly cause detonation. Now these are just examples and to specifically say what will really happen depends on the other variables. Dirty sensor elements gives less voltage at same flow.
Dirty injectors may cause a lean condition as well as fuel pressure and volume.



U4P0 J4J1
# Mass Air Transfer Function
( 15.9998, 932.145 ) ( 15.9998, 882.085 )
( 5, 932.145 ) ( 5, 882.085 )
( 4.75, 808.577 ) ( 4.6001, 717.327 )
( 4.5, 697.683 ) ( 4.19995, 568.729 )
( 4.25, 598.512 ) ( 3.80005, 443.577 )
( 4, 510.114 ) ( 3.5, 362.466 )
( 3.80005, 446.745 ) ( 3.30005, 313.989 )
( 3.6001, 389.397 ) ( 3.1001, 270.265 )
( 3.3999, 337.118 ) ( 2.8999, 230.66 )
( 3.19995, 290.86 ) ( 2.69995, 195.491 )
( 3, 249.037 ) ( 2.5, 163.173 )
( 2.80005, 211.65 ) ( 2.3999, 148.281 )
( 2.6001, 178.381 ) ( 2.30005, 134.974 )
( 2.3999, 149.232 ) ( 2.19995, 122.301 )
( 2.19995, 123.568 ) ( 2.1001, 110.894 )
( 2.1001, 112.162 ) ( 2, 100.122 )
( 2, 101.389 ) ( 1.8999, 89.9828 )
( 1.8999, 91.2501 ) ( 1.80005, 80.7944 )
( 1.80005, 82.0617 ) ( 1.69995, 72.2397 )
( 1.6001, 65.2692 ) ( 1.6001, 64.3187 )
( 1.5, 57.9818 ) ( 1.5, 57.0313 )
( 1.30005, 44.9914 ) ( 1.3999, 50.3777 )
( 1.19995, 39.2882 ) ( 1.30005, 44.3577 )
( 1, 29.4662 ) ( 1.19995, 38.9714 )
( 0.75, 19.961 ) ( 1, 29.1493 )
( 0.600098, 15.2084 ) ( 0.899902, 25.0304 )
( 0.399902, 10.4557 ) ( 0.800049, 21.2283 )
( 0, 8.87154 ) ( 0.600098, 14.5747 )
( 0.5, 11.7231 )
( 0, 11.7231 )

To modify the MAF sensor is in all practicality a bad move without telling the computer that the flow has increased via the transfer function table. Also, modified intakes will not be as effective as presumed unless the flow changes are calculated also. The best way to increase the flow to the motor and let it know is to get the system tested or get a system that has been flow profiled and includes the ability to program the PCM. You can't just "recalibrate" the MAF. Load will be incorrect. This can effect the durability of the motor especially when WOT driving is done.

These are issues that you must take into account when debating a change to the system. There are some slight risks involved and you'll have to decide.

I hope this information proves useful. Any discrepancies are my own and you can e-mail me about it. These are only the facts presented as I see them with the information I have gathered. Richard MacCutcheon

ok raise you hand if you read that whole thing..
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Old September 26th, 2006, 11:53 AM   #16
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I read enough to know that everyone else should be reading it, even if they do not fully understand it.
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Old September 26th, 2006, 12:03 PM   #17
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The original article with images can be found on this link:
ALL FORD MUSTANGS
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