Aircraft hydraulic system editing

[NigeF-51]

Hi,
In one of the aircraft I regularly fly in FSX, the hydraulic pressure is 450psi at idle and gets to the correct system pressure of 1000psi at almost max rpm, whereas the real aircraft should give at least 800psi at idle rising almost immediately to 1000psi with little throttle movement. Once at the correct pressure on the real aircraft, it is maintained by offloading the pump to maintain 1000psi and does not vary with further throttle movement.
My question is, therefore, can the aircraft be modified to reflect this by tweaking the pressures and how would I go about it? The .cfg file [Hydraulic] section correctly states the max pressure of 1000psi.
Thanks for any help,

Regards,
Nige F