While technically the most western part of the city of Los Angeles, it is not referred to as West LA. West LA is another area, about 20 minutes to the east of Pacific Palisades (with no traffic). This is where UCLA is located. West LA, and adjoining Santa Monica and Venice, is about as west as you can get where there is lots of action.
Farther east (a little bit) gets you into West Hollywood (nothing but action).