Time for the noob question of the day.
How do you know when your MAF is scaled correctly?
Is it when your LTFT/STFTs are at 0 give or take a bit?
What if this results in MAF lb/hr readings that *could* be right, but seem a little high. (36 lb/min peak on a 2.99 pulley, 3 inch intake, 17.4psi, and a mostly zeroed out LTFT). Before tweaking the MAF tables on my stage 2 tune I was seeing a peak of about 32 lb/min.
My method of MAF calibration is a little wacky, but seems to work. I just wonder whether I'm skewing my MAF readings just to appease my LTFT/STFTs. I just want to know that I'm calibrating my MAF correctly, and not fudging numbers.
This is my method, for better or worse:
1.) Copy/Paste the MAF values from my tune file to the "C" column of an excel spreadsheet, with labels. This will extend down to the "AK" column for the LSJ.
2.) Open an HPL log, convert to CSV, and copy the entire LTFT and MAF Hz columns side by side to the "A" and "B" columns of the spreadsheet.
4.) Now comes the wacky part...
The spreadsheet needs to read and average all LTFT hits within a given MAF Hz range within 300 Hz of each MAF table. For instance, I have the formula average all LTFT hits that correspond to any MAF readings between 2850--3150, and that gives me the average for the 3000 hz table.
Once I have my LTFT averages for each MAF table, I convert to decimal since LTFTs are percentages, then multiply my original MAF table value by that number to find out how much I need to add or subtract from the original value.
SO, if my original table value is 1.271, and the average LTFT for the 3000 Hz table is 2.028, I need to add 2.028% to the original, giving me 1.297.
I've run my logs through this "filter" several times, and every time I get closer and closer to zero. Its really exciting to watch it happen, but I'm a bit in the dark without confirmation that I'm doing things right.
If my method is confirmed to work, and anyone is interested, I'll clean up my excel spreadsheet and post it for all LSJ people to use.