Off the shelf maps

Iam having trouble with my ltft, after my ltft settle they are usually at +10-13 and it’s in the high cruise section 10-60 g/s according to subaru, would I be able to datalog actual mafv to actual measured airflow and compared it to the maf scaling and make the mafv match actual maf reading ? Would this be a good way to scale those areas of the maf? Iam working of an OTS map from Cobb and my maf scaling appears to be off only in that area, I’ve looked for leaks but couldn’t find any..

There are a couple of ways of dealing with this but if you're in closed loop then the easiest would be to log the LTFT and STFT added together vs MAF voltage and generate a histogram in a package such as MLVHD. You can then use this data to correct your MAF scaling.