MAF maxed out

I have recently tuned a 2019 Holden Colorado, it’s running a 2.8 Duramax, it made a 27 percent power increase but the maf maxed out at 2900 rpm and 220g/s, from my research these are not typically a limiting factor, can anyone help with this? Thanks

I suspect if it's like our domestic 2.8 the MAF calibration may have an artificial ceiling. Take a look at the calibration curve and see if it might be scaled out towards 250 g/s.