haynes manual says:

Minimum oil pressure at 80°C (176°F):
At 750 rpm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 bar (14.5 lbf/in2)
At 2000 rpm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.8 bar (40.6 lbf/in2)
Oil pressure warning lamp operates . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 to 0.5 bar (4.3 to 7.2 lbf/in2)