what is the max N/A RWHP the stock injectors can push?

 

The size of the injectors is determined by the flywheel HP, not the "RWHP".... the injector has no way of knowing how much power you're losing in the drivetrain.

With an extremely efficient tune (0.45 #/HR/HP), and running at 100% duty cycle (not recommended or even feasible), you could push the stock 24's (24.9 #/HR in the PCM) to 440 flywheelHP. Running a typical tune (0.48 BSFC) and keeping the duty cycle under 90% would limit you to about 375 flywheelHP.

And those numbers assume you are still running the stock 43.5psi differential pressure. By increasing the differential pressure to 52.7psi, you could make an additional 10% with the same injectors.