Many of the corvette guys have this problem as well.
Stock TPI motor, new injectors, (because the old ones short out), and now the BLM's are sky high, but the car runs fine. OEM prom.

I have this problem with my LB9 motor. It's 99% stock. The original injectors shorted out. I replaced them all with 19#. The car would not run past 4500 RPM's. staving for fuel. bucking, dieing at high RPM's.

Ok, I have the big cam TPI motor with N10 exhaust. I put 21# injectors in there. Car runs amazing. Full power across the entire RPM range.
Started data logging. BLM's 150+ in most cells. Int 128-130. No vacumme leaks anywhere. Idles great. Love the way it runs. But the BLM's are just very high. I added a heated O2 sensor. No change at all. The fuel pressure reg is OEM.

Why do these new injectors cause high BLM's??? I'm not running out and buring proms, as the car runs too good to mess with it. But did anyone figure this out ??

Above 128, and the ECM is adding fuel to compensate for a lean condition at a particular load and RPM. What injectors did you purchase and at what psi are the rated at 21#hr ?
You may need to start with you injector offset vs voltage tables and recalibrate the eprom. You int looks good run with it.