Radar market expanded very fast over the last decade. Therefore, different kinds of vehicle integration issues are emerging and challenge the styling, architecture and system performance. Taking up these challenges consumes tremendous amount of time and generates a lot of worries. An accurate Radar and vehicle modelling is required to investigate the best integration compromises. Electromagnetic simulations seems to be the most appropriate solution to avoid critical problems and improve radar performance in real operation. The proposed workflow is illustrated through application to an actual project using Altair HyperWorks tools FEKO and WinProp. Good correlation between simulations and measurements is observed. Finally, the benefits and challenges of this radar simulation workflow are identified and discussed.