I had meant to write this (SELBEN applies any multiplier correction to VETABLE_DMA):
MAF = {GM.VETABLE_DMA.VE}/{CALC.DAT.K}*{SAE.RPM}*{SAE.MAP.kPa}/15*{CALC.SELBEN}
(where the VE units are shorthand for g*K/kPa)
(where CALC.DAT.K is {GM.DYNAIRTMP_DMA.C}+273.15)