This paper presents mOVERS (mobile Opportunistic Vehicular Emulator for Real Scenarios), an emulator capable to recreate scalable vehicular scenarios of data gathering and content distribution in vehicular networks, which replicates the same software of the vehicular On-Board Units (OBUs), and integrates real vehicular network data such as mobility of vehicles and connectivity. This emulator works with mOVE (mobile Opportunistic VEhicular) DTN platform, and it contains a base opportunistic approach for data dissemination, that can be used to develop, test and evaluate routing mechanisms and data delivery strategies for both data gathering through vehicles, and content distribution strategies from the infrastructure to the vehicles. The results of a real rush/non-rush city-center scenario show that the proposed emulator is a solid platform to easily develop and evaluate new protocols in a variety of geographical contexts and time related analysis.