Fuel consumption of road cards has been a main issue for the global automotive industry. Engineering tools, such as wind tunnels and computational fluid dynamics (CFD), have been employed for vehicle design, intending to achieve more aerodynamic efficiency. However, wind tunnels are very expensive facilities.Conversely, CFD technique rises as the best cost-effective tool for solutions on aerodynamics. This paper presents the influences of numerics and brief analysis of the intrinsic turbulent flow over a 3D realistic car model. The objective is to provide a significant cost-benefit of numerical parameters to the automotive industry in the development of road cars.Besides the validation from an unsteady-state simulation over a full car domain, the simplification of the domain by half and the steady-state regime were found to provide an acceptable approach for automotive simulation. From the point of view of turbulence, the high concentration of turbulent kinetic energy indicate regions of high instabilities as wheelhouses, mirrors, and turbulent wake with corner vortex. These regions are relevant for research in drag reduction.Therefore, the main contributions of this paper are: (a) to present a brief discussion about regions of high instabilities and turbulent kinetic energy over the DrivAer car model, as well as (b) to outline the numerical influence on drag prediction, and consequently, state a best practice in simulation of three-dimensional realistic car mode for industrial purposes.