2 different maf's 2 different AFR's
 

when we dataloged my car last time, it looked like the maf was reading werid. AFR however was 12.8 or so. My maf for refrence is a stock one without screen.

So I put on a different maf (stock) with screen and my AFR dropped all the way down to 9.6 !

What in the world would be causing it change that much?

With my maf that was reading 12.8 the car just went 11.5 @ 116... so i dont think its bad.... But i have tried 2 other ones with screen and both make my car go dead rich.

With the stock descreened MAF you are getting more air than the MAF realizes. The MAF is telling the ECM there is less air than you are actually getting so you are getting less fuel for more air and so your AFR is not as rich.