Typically... not enough.
As for GPH, not really sure, but for pressure Ford's spec is 55psi +/- 5psi, but that is regulated pressure, not what the pump puts out. Usually a hot tune is enough to drain the pressure down a bit. Your mods will dictate what you need for a fuel system. Some guys have no problems running a better lift pump feeding their stock pump, like an AD 150 going to your stocker.
