Sim Engine is a term used to describe an element of the coding in NBA Live and other basketball video games that controls aspects that are not controlled by the user, such as the performance of players on CPU-controlled teams and the results of games between CPU-controlled teams in Dynasty and other season modes. It also determines the selection of All-Star participants and award winners, and is wholly responsible for determining the outcome of games that the user elects to simulate.
The quality and accuracy of sim engine results is paramount to many NBA Live players as it is the sim engine that determines whether or not CPU-controlled players will produce realistic statistics in games that the user does not play and that the results in a Dynasty or Season are similar to what can be expected of the team's real life counterpart. A faulty sim engine that causes undesirable results is therefore often mentioned amongst negative reactions to a game.
Sim Engine Editing
Patchers have enjoyed some success in modding the sim engine in NBA Live. By modifying the simeng.txt file using Notepad, it is possible to change the results produced by different player ratings. NBA Live 08 - notorious for its troublesome sim engine - stores data in a different file (simengin.bin). Editing this file is a less precise science and requires trial and error.