I was running lean on the low end as well. More air requires more fuel. As I stated before, I did a Gen3 swap on the car. Including the larger throttle body.
I suggest you try an adjustable FPR yourself before stating it doesn't work. The PCM has a neat way of regulating your AFR for you.
2000SilverBullet and I are both running adjustable FPR'* with great success. My car recently posted 31mpg AGAIN just over a week ago on a long freeway trip. Doesn't seem to be running rich on the low end, does it?
There are probably some applications that an adjustable FPR won't work for, but with my setup, it was the ideal solution.
Just got this via PM. Maybe it can explain things in simpler terms.
You know its funny most of the time the PCM will look at the info from the sensors and try to maintain a 14.7 to 1 ratio
This is assuming your MAF sensor is calibrated (chosen) to match the range of flow you would see from the bottom end to WOT. And assuming your fuel injectors don't go static before WOT trying to achieve it. Which is exactly WHY the adjustable FPR works. I'm only aware of two cars here on this Forum that have even tried it, and both of us love it.
Anyone else have supporting or opposing EXPERIENCES?