Tutorial: How to scale your MAF [pics]
#31
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Not sure if this helps, but I created a template Excel spreadsheet to figure the changes that needed made, based on a EvoScan log.
Directions :
1) Paste your MAF Scaling into the Template
2) Paste EvoScan Columns into template.
- FuelTrim_Mid, FuelTrim_High, AirFlow and TPS (optional)
Once the data is pasted the MAF Value (TO_BE) should calculate based on the formula given previous.
If anyone finds errors, let me know.
****I have removed the template, until I can get a better idea of which EvoScan fields to use, FuelTrim_xxx or O2feedback.
Directions :
1) Paste your MAF Scaling into the Template
2) Paste EvoScan Columns into template.
- FuelTrim_Mid, FuelTrim_High, AirFlow and TPS (optional)
Once the data is pasted the MAF Value (TO_BE) should calculate based on the formula given previous.
If anyone finds errors, let me know.
****I have removed the template, until I can get a better idea of which EvoScan fields to use, FuelTrim_xxx or O2feedback.
Last edited by fixem2; Feb 26, 2007 at 09:20 AM.
#32
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Does your scaling template actually work for you?
I'm getting values that are less than my factory.
Pre:
I looked for my 02feedback and got rid of every row with 100 value (to get rid of open loop conditions)
1. I pasted my maf values into the lookup table
2. I copied my mid, high, tps, and airflow into your template (not sure why you need tps)
Now I get kind of funky values that are sometimes less than factory.
I have it averaged out in a pivot table.
My pivot table:............................... Stock scale: .............................. Adjusted scale:
I'm getting values that are less than my factory.
Pre:
I looked for my 02feedback and got rid of every row with 100 value (to get rid of open loop conditions)
1. I pasted my maf values into the lookup table
2. I copied my mid, high, tps, and airflow into your template (not sure why you need tps)
Now I get kind of funky values that are sometimes less than factory.
I have it averaged out in a pivot table.
My pivot table:............................... Stock scale: .............................. Adjusted scale:
#33
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Sophie, I posted this on Friday night and I have been unable to see my post until now. I was using the TPS for verification and to verify I wasn't WOT. I believe this template will work, but I was using FUELTRIM_mid and High. Anything over 100 I was calling a % similiar to OBD, but from the other thread that was incorrect. Using information from the other thread I should be able to get it working. I need to edit my post and remove the template, because it was preliminary and needs work.
#34
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...but you changed the "16384" value to "1600" and so now your 1600 value changes from ~191-195 to 232... does that pose a problem? Shouldn't the independent variables be similar to what they were since you're only interested in changing the values at the lowest loads? (19 and 25)
#37
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Back up.
I changed the directory structure on www.sscustom.net and forgot these were linked.
I changed the directory structure on www.sscustom.net and forgot these were linked.
#42
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OK, so I want to do this because of my Injen/TurboXS hybrid intake set-up, and all of my mods that I will be doing in the very near future.
I read through the entire thread, and there is one question I have (Probably due to ignorance):
In doing this, can you use Evoscan to do this? Someone posted a question like this, but it was never answered. People keep mentioning an OBDII scanner/logger to look at the STFT/LTFT. I am assuming that EVOScan doesn't look at this, or at least output the data that I need to do this. Do I need a different program for OBDII logging, or is Evoscan doing it as O2 sensor feedback and Low/Med/High trims?
I read through the entire thread, and there is one question I have (Probably due to ignorance):
In doing this, can you use Evoscan to do this? Someone posted a question like this, but it was never answered. People keep mentioning an OBDII scanner/logger to look at the STFT/LTFT. I am assuming that EVOScan doesn't look at this, or at least output the data that I need to do this. Do I need a different program for OBDII logging, or is Evoscan doing it as O2 sensor feedback and Low/Med/High trims?
#44
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Please excuse my question as a neophyte, but the MAF scaling value is an 8 bit number, so 255 is largest number that can be entered. Aren't we going to max out at 255 by ~125-150Hz and just end up filling most of the table with the maximum value for the data type (assuming ~20% correction)?
Thanks,
Mike
Thanks,
Mike
#45
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If you've already tuned your AFRs with the intake on, you can probably just tune the values you hit in closed loop and it shouldn't affect the open loop fueling. Of course, if the air flow values overlap in closed and open loop then you will need to re-tune that area of your map.
I would think that if you tuned before the intake that correcting these values should put you back to where you were (fuel wise) before the tune.
My question is this:
I just tried this yesterday on a friend's IX after we installed his K&N intake (I know ...). It seems obvious that one correction % will not work across the entire map. My initial thought was to take a few samples in closed loop, such as idle and a few cruising RPMs, and attempt to create a sample curve to base the rest of the values on. Has anyone tried this method? If so, was it successful?