static 58psi, or vaccuum referenced tuning?
If you are running a high boost application and start at 58psi with a rising rate regulator, then at 15psi your injectors will see 73psi, and may even lock up. But if you start at 43psi and add 15psi, you only run the injectors at 58psi with 15psi of boost.
Just much easier on the fuel system to start with a lower base fuel pressure setting.


