Hi and welcome to Flyer Talk ptong

I presume you have separate tickets. The minimum connection UA->NZ at LAX is 3 hours. That said it is possible to connect in 2 hours 16 minutes but only if your inward flight isnt too late. UA uses T6/7/8 which is the opposite side of LAX from T2 which NZ uses. Allow 15-25 minutes to change terminals (either walk around the U, walk through the carparks or take the free shuttle). Security queues at T2 are normally very long (that time of day), with even a queue just to join the security queue. I expect a minimum of 1 hour to get through this (and up to 90 minutes).