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Old 01-23-2014, 09:05 AM   #3
AdrianG
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Join Date: Aug 2013
Drives: '08 STi Hatch, '11 Outback 3.6R
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I have been trying to find the correct MAF reading in CFM, so far I've tried two and while the outputs correlate with eachother, they are not identical. They follow the trend I expect but they seem like they are reading low, I would expect more airflow given the condition.

Here's my log, more or less flat-foot in 5th gear on the highway:
http://datazap.me/u/adriang/ots-stag...7&zoom=239-430

"maf default" is the default address from the sample logcfg.txt:

Code:
paramname = MAF_default		
paramid = 0xFFF8DB90				
isfloat = 1
and "maf tdd" is from the output in the top post provided by Td-d:

Code:
paramname = MAF_Tdd
paramid = 0xFFF89114
isfloat = 1

With @Td-d's help I see now that the AFR as listed above is the LAMBDA value, and we can get the ratio by multiplying the provided value by 14.7. This math can be applied on the OP2 directly, as such:
Code:
paramname = AFR
paramid = 0xFFF8932C
isfloat = 1
scalingrpn = x,14.7,*


I've confirmed now with the correct data type that gear and gear_calculated work. Thanks Td-d for clarifying that they are 8 bit values.

Funny enough, one reads neutral as 6, the other reads neutral as 0...

It is my understanding that reading the RAM parameters is much faster and more efficient, using gear at 0xFFF895D9 is my preference.

Code:
paramname = gear
paramid = 0xFFF895D9
databits = 8

paramname = gear_calculated
paramid = 0xFFF895DA
databits = 8

Last edited by AdrianG; 01-23-2014 at 04:47 PM. Reason: info added/clarified
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