A vehicle simulation system includes a first simulation model that when executed simulates a software ring along with other software of a vehicle module. The vehicle simulation system further includes a second simulation model of the software ring. A bypass switch that has a first state and a second state. A bypass switching module switches the bypass switch between the first simulation model and the second simulation model based on a bypass signal and a ring enabling signal. A simulation control module executes code of a vehicle simulation model including software in-the-loop (SIL) testing of a selected one of the first simulation model and the second simulation model based on state of the bypass switch.