Recently, the networking and automobile industry has witnessed the emergence of vehicular networks which were developed to provide safety and non-safety Intelligent Transportation System (ITS) applications. The provision of seamless mobility and session continuity during handovers is critical for better Quality of Service (QoS) provisioning in vehicular networks. In this paper, we propose a scheme meant to improve handover performance in IP-based vehicular networks by maximising the correct handover initiation probability and increasing data throughput during inter-subnet handovers. We analyse the effects of mobile node's speed and direction of motion on both correct handover probability and data throughput using numerical results.