so i started to play real tuning games with the injection. at full 60psi boost the smoke cleaned up so i suspect the injectors are sized close to properly. my research also suggests that. i know they do still put out extra fuel though since i have a dyno run where they fogged the air filter with NOS and it did make more power. 501hp to be exact. now down low they are a bit big at min pump output so i think no matter what she'll fart if i bog it on a start or smash the throttle at low R's. however, the middle ground could use some work.
i was told it had the stock AFC (air fuel control) spring in it, so that would bring in full fuel by 18psi. this spring acts against a diaphragm driven by the boost psi to compensate fuel.
needless to say it smoked a lot, and was way over-fueled most of the time. well i bought a 0-700lb spring pressure tester and characterized the stock spring. then ordered 5 different springs with the same OD and height, but different spring constants. this should let me pick a nice rate of change. i can also tighten the pre-load to adjust where it starts moving.
my thought was if i'm running 3.75x more psi, and i wanted the same travel in the diaphragm, i needed a 3.75x stiffer spring rate. functionally i don't think that's working though because of the minimum preload and stopping too much fuel down low. first test was the stiffest spring i got, and i couldn't quite get to full boost, so fueling seams limited up top. basically can't get the fuel to get the boost to move the diaphragm for more fuel.
and that's with minimum preload. next spring is a mid range stiffness with more preload to start ... stay tuned.