That pressure 2-4 psi is needed at the IP after filter.
So, where the LP is located, you need slightly higher since there is efficiency factor like it will loose 50% of the capability after getting up there. Just my thought. May be I am overthinking it.
The 93 LP is spec for 9-14 psi but I know the quality is not there because it can go to 0 at WOT.
Please do try it and see if it can hold that pressure at the IP steady.