The engine block is a crucial component of internal combustion engines since it provides the source of power for the vehicle. The engine block is a solid cast element that contains the cylinders and their related components inside a cooled and lubricated crankcase. The majority of engine blocks are cast iron, a brittle rich material that can sustain greater variations and weights while also being vibration resistant. Energy is changed from potential chemical energy to mechanical energy in this step, which is heat produced from burning fuel in the form of mechanical energy. A large amount of energy may be lost during the firing of an engine. This must be assessed using CFD prediction techniques. For starters, significant thermal and structural stresses may be produced over the cylinder blocks and pistons. Prior to the fabrication of the specific Internal Combustion engine, the structural and thermal analysis aids in the failure analysis. The solid modeller Parametric-Creo is used to create the current and new engine block models. This technical chapter will cover the simulation and analysis of the structural and thermal consequences of each specified bore piston and cylinder block model. The effective stress and temperature analysis using the finite element method will be performed using current tools such as ANSYS workbench, ADSL, and Deform 3D, with the processes and analytical functions described utilising supplementary literature theories, which can be found here.