This comprehensive Stage 1 calibration refines every facet of the 1.6 CRDi 16V engine management system to deliver a substantial improvement in throttle response, mid-range torque and overall driving refinement. By reshaping turbo boost control maps, we have achieved a more immediate and linear torque delivery from idle to peak, significantly reducing lag while maintaining safe pressure limits. Injection timing and rail pressure curves are carefully tuned to optimise combustion efficiency, reducing particulate formation and lowering emissions without compromising power delivery. Adaptive EGR flow calibration ensures stable regeneration cycles and consistent exhaust gas temperatures, which translates into longer DPF life and reduced maintenance intervals. The throttle mapping is smoothed to eliminate any flat spots when transitioning from part-load to full-load, giving the driver a seamless and predictable driving experience. Gearshift logic in the 5-speed manual transmission has been adapted to match the enhanced torque curve, resulting in crisper, more confident shifts under load. Diagnostic and fault-monitoring routines remain fully intact, ensuring compatibility with dealer-level scan tools and preserving serviceability. Fuel economy is also addressed through subtle adjustments in fuel map gradients, offering a balanced trade-off between performance and consumption ideal for both urban commuting and light-duty hauling. Tested on a professional dynamometer and validated against OEM safety margins, this calibration transforms the Cee’d into a more responsive, efficient and engaging vehicle without affecting long-term durability.