Abstract
EDCRASH is a collision reconstruction computer program used to analyse motor vehicle collisions. One analysis that the program does is to determine the speed change of the vehicle during the impact based mainly on crush deformation and vehicle stiffness properties. The program requires input of stiffness properties in imperial units. This paper looks at available crash test data for Australian produced cars, theory in determining their frontal stiffness, calculation and results of frontal stiffness parameters for these vehicles and finally the computed accuracy of speed change from damage using EDCRASH with calculated and default stiffness parameters.