Effective thermal management in internal combustion engines is essential for meeting increasingly stringent emissions regulations and achieving fuel efficiency improvements. This study introduces a novel and comprehensive approach to optimize engine thermal management by addressing key system components, including coolant circuit design, Integrated Thermal Management Module (ITM) control strategies, port-specific flow management, zero-flow operation techniques, and HVAC (Heating, Ventilation, and Air Conditioning) settings standardization. Unlike previously published works, this study focuses on reducing coolant circuit thermal mass to accelerate engine and component warm-up, refining ITM control logic through linear mapping and advanced signal filtering for precision, and enhancing zero-flow operation for minimizing lubricant oil dilution during start-up and reducing heat loss under low ambient conditions. Additional optimizations include port-specific adjustments and radiator flow distribution strategies to improve system responsiveness and fuel economy. Standardized HVAC configurations were implemented to ensure reproducibility across WLTP vehicle and bench testing scenarios. The methodology validated key improvements through rigorous testing on a newly developed engine platform and demonstrated scalability by successfully integrating these measures into vehicles designed to comply with EU7 regulations. Results indicate substantial gains in warm-up performance, coolant temperature control stability, energy efficiency, and regulatory compliance. Furthermore, these advancements underscore their practical application for automakers seeking novel solutions to meet evolving environmental standards and enhance market competitiveness. Overall, this study presents a set of scalable and widely applicable strategies for modern spark-ignition engines, supporting both new engine development and optimization of existing engines, while addressing global fuel-efficiency and emissions challenges effectively.