Haha but youre not informing him how much harder tunerpro is to learn vs the simplicity of HPT, and the interface required for tunerpro to the pcm.
Nothing is free.
I use tunerpro on occasion for .xdf creation for custom parameters on PCMs im writing to.. its a mess if youre just getting into it. Hptuners is the best bet, best price point.... lots of online tutorials for it... gen 3 LS is easy peezy
Let us /me / whoever know if you ever dive in and need help there
Hes right though, MAFs have different part numbers that correspond with certain tube diameter, tube length, and bends and also have relationship to the MAF airflow curve which is metered by commonly grams of air per second measurements....
Changing MAF p/ns or just generalizing mafs from one to the other may yield bad results.
Ive seen first hand, just a change in airflow angle, or filter size, or what have you, and EVEN the IAT location all play a big factor in airmass calculation for the motor which is very much relevant to spark degree/retard on gen 3 .
Each sensor p/n has a corresponding sensor curve over 0-5 volts or 0 -1millivolts that belongs in its corresponding PCM map and OS for that particular vehicle.
That all ultimately affects LT/ST % at the end.
Ive seen it many times in my tuning journey.. you got these guys (not saying its you) with a mismatched pedal, throttle body, generic sensors , mis matched and retuned PCMs, etc and so forth and have all these Fuel trim issues... the stuff matters in the calibration
Down to the oil viscosity and the knock sensor specifications for the particular vehicle and application from GM
Ive combed thru a couple PCMs with customers taking everything from their junkyard PCM and making all the scales and calibrations and tables match their particular application or close to it... its A LOT lol
The computers just have enough intelligence and flexibility in their management , you can do everything wrong and it still runs halfway right.