pressure -- I would guess starting at around 500psi given the lack of volume in the mini. -- work it 100 psi each way from there.
also: make sure the jam nut is snug and the valve is aligned correctly...
Ive seen an xtra oring on the loose back in a valve chamber create havok
--- ¡¡¡pıɐ-ןooʞ ǝɥʇ ʞuıɹp ʇ,uop---