The difference between 1000HP at 1.0 pf anf 900hp at .8 pf is that the 1000 hp motor at 1.0 pf will not draw any vars, whereas the 900hp motor at .8 pf will draw 503 K-Vars at full load.
Another thing is that the nameplate rating states the pf at which the motor can be run continously at full...