Multi-core processors have been increasingly used to reduce power consumption and improve performance in embedded systems. In addition, a use of Model-Based Development has been increasing. Relative to these trends, Model-Based Parallelizer (MBP) has an essential role in parallelizing applications (i.e., Simulink blocks). MBP maps Simulink blocks to cores at the model level using various information. Generally, mapping blocks to cores is considered an NP-hard graph optimization problem; thus, MBP uses a heuristic method to solve it. A heuristic method can solve problems at high speed, but it is often not accurate. Therefore, this paper proposes two methods to improve results of MBP. The first method remaps blocks to cores based on the results of MBP. The second method determines an execution order that can finish the entire process faster than existing methods. Evaluations demonstrate that the proposed methods can obtain better results than existing methods in terms of Speedup and Load-Balancing.