I still haven't pulled the calibration file from my vehicle, since I am waiting on a cable.
I have been comparing bin files from fbodytech, I haven't found the latest calibration file for my vehicle anywhere else. And I certainly don't want to pay a dealership to reflash my PCM for $100 (I doubt they would flash me the 9C1 shift points either).
The latest official calibration for my 1995 Roadmaster w/ tow package is:
1995 5.7L 2.93 AXLE TRAILER TOW
NEW CALIBRATION NUMBER
The file, 16243171.bin, I found on fbodytech; which seems to be very legitimate.
After browsing this file using tunerpro, I noticed the MAF is disabled.
I also compared the latest files for the 9C1 and the Impala ss. It seems to me that only the Impala has the MAF enabled. They all have MAF diagnostic enabled (code 48). And I know they all have an actual MAF sensor, like all of my Roadmaster's before. But if the MAF is disabled, then the PCM uses only Speed Density mode for air/fuel metering, and the MAF sensor would be pointless to even be installed.
I am new to tuning, but I would think MAF metering would be the most accurate and preferred method if your keeping stuff relatively stock (I'm not racing this thing).
The reason for my concern is that I have the K&N intake on my car, naturally I assume this has an effect on the airflow into my engine. If the MAF sensor is used I assume the PCM would sense this change in airflow characteristics and adjust accordingly. If the MAF is not used then the PCM refers to the Volumetric Efficiency Table and uses the MAP sensor. Now I am sure the MAP readings would also notice and reflect the changes caused by the new air cleaner. But I still have one question, does that mean the VE table should be adjusted? Basically what I want to know, after assuming the only change done to an engine is a higher flowing air intake, then does this effect the volumetric efficiency of the engine? I assume it's an easy "Yes!" to that question, but in the case of my K&N filter on my Roadmaster with stock engine, would it even make enough of a difference for me to be concerned with the VE table?
And if I am correct about the factory disabling the MAF sensor, then what would be their thinking behind such a thing? They must think their VE table is on point.
I also installed a cat-back exhaust with stock manifolds and converters. I'm sure the exhaust effects the VE of an engine as well.
Last edited by chillrobb; 01-01-2017 at 03:22 PM.