An analog computer simulation development for a passenger car foundation braking system is presented. A brake control system is added to the simulation. As the hardware for the brake control system is developed it is substituted into the simulation along with components of the foundation brake system. This mixture is a “physical simulation” where the analog simulation is reduced to represent only the vehicle and the road with appropriate interface elements for the actual brake and control system hardware.The discussion includes the studies conducted using physical simulation for tolerance study of vehicle characteristics as well as the foundation brake system and control system parameters. Results which validate the model are presented.In conclusion, the advantages of this approach which supports the development of an advanced brake control system are discussed.