One of the main objectives of accident reconstruction research is to determine vehicle speed before impact. There are several types of research to determine vehicle speed before impact, because it depends on the type of impact and the geometrical shape of the obstacle. This research is usually valid for a computer simulation program, for example „PC Crash“ which represents a „TMeasy“ handling tire model based on a semi-physical model. Due to the increase in computing power, it is possible to develop tire models that are more complex and able to deal with different operating conditions for example finite element method. This article analyzes the vehicle‘s speed loss during a tire‘s impacts obstacle. The analysis is presented as the experimental research of tire parameters (forces, contact path, speed loss, tire deformation) during the impact obstacle. The vehicle handling performance is directly related to the tire-obstacle (road) contact. Contact path, vertical and horizontal forces on loads, forces during impact are analyzed and experimental research results valid on computer simulation and compares.