running really lean at idle and at end of 1/4.. someone help
Anyway, you'll need to do some logging with your original stock MAF and then your new MAF and then compare the reported flow rates. I had to rescale my MAF up by 16% to report the same g/sec as the stock MAF. My A4 trans shifts were dead soft with the stock MAF calibration and new MAF, but once I rescalled it, it shifts like normal. There are however some issues with the scalling in the 2000hz-3000hz range. I'm trying to resolve these problems, but am just lacking time to get it done.As for running lean at the end of the quarter mile, when you lift off the throttle the PCM is reporting similar MAP conditions to decellerating downhill and there is a function for the PCM to cut off fuel under these conditions. I don't know how you modify this function yet. Perhaps someone else can chime in. If your not running any CATS, then turn off COTS with Edit. It sounds to me like your PCM is dumping fuel when Catalytic Over Temp (COTS) is enabled. Commanded AFR typically dives to 11.6:1 when COTS kicks in. If you are running CATS, DO NOT DISABLE COTS! It'll fry your CATS! You can instead try raising the COTS enabled temp by 100º across the range. It will help to delay the point at which COTS is commanded by the PCM.
Overall, it sounds to me like your MAF is causing the large swings in LTFTs and you need to add some fuel when in PE.
Good luck,
Richard

