Tire-blowout impacts vehicle stability and creates challenges to vehicle control. To accurately evaluate the impact of tire blowout in different driving scenarios, a new tire blowout model is developed in this work with explicit considerations of the tire vertical load redistribution and self-alignment torque (SAT). A two-stage vertical force redistribution model is employed for the vertical load variations, instead of the one-stage model in literature. Moreover, the SAT is formulated and the impact on the steering system is investigated. The developed tire blowout model is validated through both simulation and experiment using a scaled test vehicle. The results indicate that the proposed tire blowout model can evaluate the tire blowout impacts on vehicle dynamics more accurately, which will benefit the evaluation of tire blowout impact and the future development on model-based fault tolerant control.