I have a stock b16a head with gsr cams. I have an aem fpr and fuel rail, it's turned up to about 50 psi and i was wondering is it ok to run these injectors so hard? Is there a chance they may fail?

 

at 50 psi, not a big chance of failure. Although you are pushing the injectors a bit harder than stock pressure, stock injectors can generally handle about 75%-80% duty cycle. If you really wanted to solve the problem, purchase some 270-310cc injectors and fuel pressure at 50 psi static pressure. This would be a better set up than just taxing your stock injectors with the extra fuel pressure.