Fuel Pressure Regulator?

[deleted]

Hi,
I have a 1:1 Fuel Pressure Regulator on an OBDI P72 GSR motor. Since the ECU has a long term fuel mixture trim, will it negate any changes to the air/fuel ratio made by changing the fuel pressure using the FPR? I know a lot of people use an FPR to change air/fuel but does that mean their changes would only be short term before the computer learns and adjusts?

Thanks.
-Cliff