I have a similar issue with my car and a mates car.
When I try to tune the injectors to a different fuel pressure or when I have different injectors and fuel pressure I get decent lambda on idle but goes very rich when the throttle is touched.
I've checked the fuel pressure and it is rock solid (using a GFB FPR), disabled closed loop fuel.
STFT, LTFT and commanded lambda is dead on 1.00. Also when I data log the the injector pulse width hardly changes (1.6667% to 1.9444% duty cycle)
I'm stumped at the moment, I've checked everything, gone through all the forum posts and tried everything I can think of, but I know I'm missing something.
Any help would be very greatly appreciated!
Video