MAF Scaling Table in grams/second
Dec 27, 2009, 03:33 PM
#31
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Criptballer:
When you modify anything upstream or down stream from maf sensor it throws of maf reading. Air mass will now flow differently through maf sensor housing which will either favor more or less air flow, and in the case of the evo X..... most aftermarket intake systems i have seen actually have a whole new maf housing which is most likey larger which will read alot different than stock unit which is calibrated from factory to read with given diameter of housing. So larger housing would have a maf sensor capture less of whats actually going into engine, which would give you a leaner condition which the o2 sensor would pick up in closed loop and add fuel to compensate. make sense?
When you modify anything upstream or down stream from maf sensor it throws of maf reading. Air mass will now flow differently through maf sensor housing which will either favor more or less air flow, and in the case of the evo X..... most aftermarket intake systems i have seen actually have a whole new maf housing which is most likey larger which will read alot different than stock unit which is calibrated from factory to read with given diameter of housing. So larger housing would have a maf sensor capture less of whats actually going into engine, which would give you a leaner condition which the o2 sensor would pick up in closed loop and add fuel to compensate. make sense?
and by adding or taking away fuel to compensate you have to adjust your LTFT and STFT just like i said right. and what intake gives you a different MAF housing and/or sensor, i tried looking for one but couldn't find it? also i couldn't find an actual picture of the actual MAF sensor in our cars to see if its built into it like this, and i really don't want to disassemble my intake to find out.
because if the actual sensor remains the same size then no matter what "housing" it's on or how big it is then it's still going to be the same, because the sensor itself is the same size. does that make sense? also, do we know the equation for the MAF, or what exactly are you adding when you say, i increased the values by 10%? what did you increase?
i guess my biggest question is, could changing the intake affect the timing maps or how the ecu sees the timing, or anything to do with it? whether it has something to do with the changes in MAF readings or actual CFM?
Dec 27, 2009, 05:03 PM
#33
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I looked up the code that Tepra gave in HZ and your code in g/s and the addresses are different. I have no idea which one is the correct one:
Here is Tephra's
Add to 5268xxx.xml
<table name="MAF Scaling Part 1" address="5753a">
<table name="Volts" address="615ea"/>
</table>
<table name="MAF Scaling Part 2" address="57592">
<table name="Volts" address="61642"/>
</table>
<table name="MAF Scaling Part 3" address="575ea">
<table name="Volts" address="6169a"/>
</table>
And here is yours:
Add to 52680015.xml
<table name="MAF Compensation" address="5753a">
<table name="Volts" address="615ea"/>
</table>
<table name="MAF Compensation #2" address="5758a">
<table name="Volts" address="6163a"/>
</table>
<table name="MAF Compensation #3" address="575da">
<table name="Volts" address="6168a"/>
</table>
Here is Tephra's
Add to 5268xxx.xml
<table name="MAF Scaling Part 1" address="5753a">
<table name="Volts" address="615ea"/>
</table>
<table name="MAF Scaling Part 2" address="57592">
<table name="Volts" address="61642"/>
</table>
<table name="MAF Scaling Part 3" address="575ea">
<table name="Volts" address="6169a"/>
</table>
And here is yours:
Add to 52680015.xml
<table name="MAF Compensation" address="5753a">
<table name="Volts" address="615ea"/>
</table>
<table name="MAF Compensation #2" address="5758a">
<table name="Volts" address="6163a"/>
</table>
<table name="MAF Compensation #3" address="575da">
<table name="Volts" address="6168a"/>
</table>
Edit: I clicked the show incomplete tables, and it pops up in gray (I did get rid of level="1"). When I click on the table, a pop up says the table is invalid or incomplete. Any thoughts?
Last edited by boostin20; Dec 27, 2009 at 05:17 PM.
Dec 27, 2009, 05:39 PM
#34
Hmmm the tables came up for me just fine. There different references because the table is broken into 3 segments due to being so long, and I think in the above examples they are breaking the table up into different sized portions. You have to adjust the "Evoxbase.xml" as well as the "specific rom ID.xml" with matching segmenting or it won't work right.
As for the sensor size, sure it can stay the same, but if you change the diameter of the flow sensor housing from 2.8" to 3.0" it will slightly slow down the CFM flow through the piping past that sensor as the diameter gets larger. The AMS 3" intake is one of the upgrades that increases the diameter of the airflow sensor housing but it's within the Evo X's range of self adjustment for closed loop (LTFT's) and will slightly lean the car out for open loop.
You are best off compensating for the change with MAF Scaling although for smaller changes adjusting the Injector Scaling when dialing in larger injectors seemed to work fine before we had that MAF Scaling table.
As for the sensor size, sure it can stay the same, but if you change the diameter of the flow sensor housing from 2.8" to 3.0" it will slightly slow down the CFM flow through the piping past that sensor as the diameter gets larger. The AMS 3" intake is one of the upgrades that increases the diameter of the airflow sensor housing but it's within the Evo X's range of self adjustment for closed loop (LTFT's) and will slightly lean the car out for open loop.
You are best off compensating for the change with MAF Scaling although for smaller changes adjusting the Injector Scaling when dialing in larger injectors seemed to work fine before we had that MAF Scaling table.
Last edited by Hiboost; Dec 27, 2009 at 05:43 PM.
Dec 27, 2009, 06:54 PM
#36
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Ok, so i looked a bit closer and in the Misc table, i do see maf scaling part 1, maf 2 etc. but they are greyed out and when i click on them this is what i get:
"The Current map description is invalid or imcomplete. Please edit the map description to fix problem and the map will be viewable again."
i look back at files and see if i can get the logic down, something must be out of line.
R
"The Current map description is invalid or imcomplete. Please edit the map description to fix problem and the map will be viewable again."
i look back at files and see if i can get the logic down, something must be out of line.
R
Dec 27, 2009, 07:04 PM
#37
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Ok, so i looked a bit closer and in the Misc table, i do see maf scaling part 1, maf 2 etc. but they are greyed out and when i click on them this is what i get:
"The Current map description is invalid or imcomplete. Please edit the map description to fix problem and the map will be viewable again."
i look back at files and see if i can get the logic down, something must be out of line.
R
"The Current map description is invalid or imcomplete. Please edit the map description to fix problem and the map will be viewable again."
i look back at files and see if i can get the logic down, something must be out of line.
R
Code:
<scaling name="MAFVoltScaling" units="units" toexpr="x*5/1024" frexpr="x*1024/5" format="%.3f" min="0" max="5" inc="1" storagetype="uint16" endian="big"/>
Last edited by boostin20; Dec 27, 2009 at 07:26 PM.
Jan 11, 2010, 09:18 AM
#41
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Anyone have the proper XML to define the maf scaling table properly for ROM 55570005? I have the proper code for it in the evo10base..tried the 52680015 definition but the table displays incorrectly in Ecuflash. Thanks
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