A vehicle system dynamics model is presented that captures the essential braking and handling behavior of a passenger car and runs faster than real-time on a 1998 Pentium 233 MHz laptop computer. The simulation code was generated with the AutoSim multibody code generator and linked with C functions that communicate with braking hardware to create a real-time simulation (RTS) with hardware in the loop (HITL). Techniques are described that were used to allow the simulation program to work with HITL. The model (without controller) was also integrated with the Simulink environment to provide a design tool for control engineers.