Re: Idea for 2 bar MAP sensor hack
Posted: Fri Jan 24, 2020 3:21 am
Jim,
This is where you will have to log and play with it to figure out where things are at with your new MAP sensor and revised scalar / offset values. Basically, log it while running, but try to keep your foot out of the throttle. You will then be able to see what MAP value the PCM is reading, and the corresponding grams/cyl for a given condition. Use these values to modify your tune for VE and spark.
I tried to show what the "equivalent" MAP reading would be for a given set of scalar / offset values in the spreadsheet images in my first post. You can do the same so that you have an idea of how to translate your readings. There are also equations for calculating air flow based: this is an example using the 6L displacement.
Calc_MAF_SD(grams/sec) = VE(%) * [5.968(L) * 61.024 * RPM * MAP(kPa)] / [(IAT(C) + 273.15) * 212544]
Here's how to get from grams/sec to grams/cyl
CYLAIR(gram/cyl) = MAF (grams/sec) * 15 / RPM
This is where you will have to log and play with it to figure out where things are at with your new MAP sensor and revised scalar / offset values. Basically, log it while running, but try to keep your foot out of the throttle. You will then be able to see what MAP value the PCM is reading, and the corresponding grams/cyl for a given condition. Use these values to modify your tune for VE and spark.
I tried to show what the "equivalent" MAP reading would be for a given set of scalar / offset values in the spreadsheet images in my first post. You can do the same so that you have an idea of how to translate your readings. There are also equations for calculating air flow based: this is an example using the 6L displacement.
Calc_MAF_SD(grams/sec) = VE(%) * [5.968(L) * 61.024 * RPM * MAP(kPa)] / [(IAT(C) + 273.15) * 212544]
Here's how to get from grams/sec to grams/cyl
CYLAIR(gram/cyl) = MAF (grams/sec) * 15 / RPM