100762Ultra High PCP Diesel EngineClosedCollaborative R&DInnovate UKHeavy duty vehicles account for approximately 8% of UK transport CO2 production. A fully-electric, battery-powered heavy duty vehicle is hard to envisage and so the challenge for the HD industry is one of efficiency gains, whether to the engine or to the vehicle-plus-drivetrain (including hybrids). One way of improving diesel engine efficiency is by increasing its peak cylinder pressure capability thereby allowing more advanced injection timing. The Ultra-High Peak Cylinder Pressure Heavy Duty Diesel Engine programme is developing, harmonising and applying advanced simulation tools to design and manufacture an engine with 30% up-rated cylinder pressure capability. Additionally, novel multidisciplinary optimisation tools are being harnessed to ensure near optimal functionality of the end product, and to help solve this complex design-for-manufacture problem. As outcomes of this proposed programme, the simulation-driven processes and production of the demonstration engines will represent a significant improvement over the current state in terms of both time and cost. These step changes in performance and development costs are complemented by the reduced CO2 of between 2 - 8% per engine that will be realised during the functional life of the product.