Ahem, I beg to differ with YOU.
There is ZERO PCM support for the GXP. Nobody has cracked it, and nobody has wanted to invest in being the first car.
Without a PCM, you're not going to make much power out of stuff like that.
When I say there'* not much out there, I speak from experience. Please also try to keep in mind that most GXP'* here are still under factory warranty, and please also try to remember that they are FWD, not RWD.
And once again, you are OFF TOPIC. This is your last warning. This topic is about a MAF. You've been warned 5 times in 4 days now.