In regards to oil
05-26-2009, 06:32 AM
#22
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[quote=Stevecooper;6230805]
I suspect we may be arguing semantics here, and that you are equating the voltage output of Ford MAFs with the term "counts"--which I have only heard applied to the GM MAF's output frequency...
GM MAFS work differently (than nearly everyone else's I believe) and do output a "count", actually a waveform with of frequency between 0Hz to 12kHz, that represents air flow mass. I have heard this frequency often referred to as the "MAF count", as in frequency count, in GM tuning circles.
However, Ford MAFs, unlike GM's, do not produce a waveform output, but rather a DC voltage output of 0.0V to 5.0V, representing the air flow's mass.
The available EECV PIDs return either kg/h, g/s (derived from the transfer function; PIDs 0110 and 1671), or Volts (PIDs 1177 and 1633) as input from the MAF. The voltage value is useful as it will let you know if the MAF is pegging...
GM MAFS work differently (than nearly everyone else's I believe) and do output a "count", actually a waveform with of frequency between 0Hz to 12kHz, that represents air flow mass. I have heard this frequency often referred to as the "MAF count", as in frequency count, in GM tuning circles.
However, Ford MAFs, unlike GM's, do not produce a waveform output, but rather a DC voltage output of 0.0V to 5.0V, representing the air flow's mass.
The available EECV PIDs return either kg/h, g/s (derived from the transfer function; PIDs 0110 and 1671), or Volts (PIDs 1177 and 1633) as input from the MAF. The voltage value is useful as it will let you know if the MAF is pegging...
05-26-2009, 08:33 AM
#23
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Join Date: Aug 2008
Location: Oklahoma
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[QUOTE=cliffyk;6231422]
I suspect we may be arguing semantics here, and that you are equating the voltage output of Ford MAFs with the term "counts"--which I have only heard applied to the GM MAF's output frequency...
GM MAFS work differently (than nearly everyone else's I believe) and do output a "count", actually a waveform with of frequency between 0Hz to 12kHz, that represents air flow mass. I have heard this frequency often referred to as the "MAF count", as in frequency count, in GM tuning circles.
However, Ford MAFs, unlike GM's, do not produce a waveform output, but rather a DC voltage output of 0.0V to 5.0V, representing the air flow's mass.
The available EECV PIDs return either kg/h, g/s (derived from the transfer function; PIDs 0110 and 1671), or Volts (PIDs 1177 and 1633) as input from the MAF. The voltage value is useful as it will let you know if the MAF is pegging...
This is true, the MAF will also peg at 1023 counts. Interesting read about the GM style sensors not something I have ever needed to know. I am not sure how the computer (and or SCT's software) reference counts but its sure there. Its a log able PID and on most cars its referenced in the transfer function table. Either way 0-1023 counts or 0-5V pretty much the same thing.
I'll see if I can't snap a few screen shots.
I suspect we may be arguing semantics here, and that you are equating the voltage output of Ford MAFs with the term "counts"--which I have only heard applied to the GM MAF's output frequency...
GM MAFS work differently (than nearly everyone else's I believe) and do output a "count", actually a waveform with of frequency between 0Hz to 12kHz, that represents air flow mass. I have heard this frequency often referred to as the "MAF count", as in frequency count, in GM tuning circles.
However, Ford MAFs, unlike GM's, do not produce a waveform output, but rather a DC voltage output of 0.0V to 5.0V, representing the air flow's mass.
The available EECV PIDs return either kg/h, g/s (derived from the transfer function; PIDs 0110 and 1671), or Volts (PIDs 1177 and 1633) as input from the MAF. The voltage value is useful as it will let you know if the MAF is pegging...
I'll see if I can't snap a few screen shots.
05-26-2009, 09:38 AM
#25
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Join Date: Aug 2008
Location: Oklahoma
Posts: 912
[QUOTE=Stevecooper;6231540]
This is true, the MAF will also peg at 1023 counts. Interesting read about the GM style sensors not something I have ever needed to know. I am not sure how the computer (and or SCT's software) reference counts but its sure there. Its a log able PID and on most cars its referenced in the transfer function table. Either way 0-1023 counts or 0-5V pretty much the same thing.
I'll see if I can't snap a few screen shots.
This is true, the MAF will also peg at 1023 counts. Interesting read about the GM style sensors not something I have ever needed to know. I am not sure how the computer (and or SCT's software) reference counts but its sure there. Its a log able PID and on most cars its referenced in the transfer function table. Either way 0-1023 counts or 0-5V pretty much the same thing.
I'll see if I can't snap a few screen shots.
05-26-2009, 10:43 AM
#26
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Ah, that's the raw digital value reported by the PIDs, and is the digital output value of the PCM's 10-bit ADC (2^10 = 1024, Analog to Digital Converter) for the MAF input.
This is why even though the MAF can output more than 5.0V, the PCM will only recognise 4.99...
In DeltaForce the MAF Tranfer Function is entered in Volts vs, flow...
This is why even though the MAF can output more than 5.0V, the PCM will only recognise 4.99...
In DeltaForce the MAF Tranfer Function is entered in Volts vs, flow...
Last edited by cliffyk; 05-26-2009 at 10:49 AM.
05-26-2009, 10:52 AM
#27
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Location: Oklahoma
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Does the sniper software only give you a 0-5 volt reference? I always wanted to try there kit out, do you know if they have something for a Lincoln LS?
05-26-2009, 11:09 AM
#28
So the lightning maf sensor will work, correct??? So i can retune the maf to read for stock injectors??? And cobras run 6qts of oil as well...and even though the blower has its own oil, that still doesnt account for the fact that cobras have twice the valvetrain as gt's do. So i think im gonna put a little bit more oil...just not 6qts because thats how much i had in there before and my motor feels like its more lively now with not so much oil in it. so maybe 5.25-5.5qts and call it a day.
Last edited by teej281; 05-26-2009 at 11:13 AM.
05-26-2009, 11:34 AM
#29
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Join Date: Aug 2008
Location: Oklahoma
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So the lightning maf sensor will work, correct??? So i can retune the maf to read for stock injectors??? And cobras run 6qts of oil as well...and even though the blower has its own oil, that still doesnt account for the fact that cobras have twice the valvetrain as gt's do. So i think im gonna put a little bit more oil...just not 6qts because thats how much i had in there before and my motor feels like its more lively now with not so much oil in it. so maybe 5.25-5.5qts and call it a day.
05-26-2009, 06:52 PM
#30
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^ +1, MAFs are not calibrated to particular injector size. They are calibrated to allow oversize injectors to work with a specific OEM tune. This is done by lying to the ECU about how much air (the lie is less air) is being drawn in--if the lie is big enough all sorts of other problems will pop as ECUs that use MAFs use the intake air mass values to calculate a number of other factors (most critically load) used in setting fueling and timing.
When the lie reaches a certain point the load is calculated too low and the PCU adjusts the AFR and timing for what it thinks is a lower load than the actual load (too lean, and too much advance)--can you say "destructive detonation"?
They are a kludge left over from the days when you could not practicably modify an OEM tune. Now you just program the tune with the transfer function of the new MAF, and set the low and high injector slopes to values matching the installed injectors, and tweak from there...
When the lie reaches a certain point the load is calculated too low and the PCU adjusts the AFR and timing for what it thinks is a lower load than the actual load (too lean, and too much advance)--can you say "destructive detonation"?
They are a kludge left over from the days when you could not practicably modify an OEM tune. Now you just program the tune with the transfer function of the new MAF, and set the low and high injector slopes to values matching the installed injectors, and tweak from there...